United States Busway-Bus Duct Market Report 2018

March 2018 | 123 pages | ID: UD19FAB92A0EN
QYResearch

Abstracts

In this report, the United States Busway-Bus Duct market is valued at USD XX million in 2017 and is expected to reach USD XX million by the end of 2025, growing at a CAGR of XX% between 2017 and 2025.

Geographically, this report splits the United States market into seven regions:

• The West
• Southwest
• The Middle Atlantic
• New England
• The South
• The Midwest
• with sales (volume), revenue (value), market share and growth rate of Busway-Bus Duct in these regions, from 2013 to 2025 (forecast).

United States Busway-Bus Duct market competition by top manufacturers/players, with Busway-Bus Duct sales volume, price, revenue (Million USD) and market share for each manufacturer/player; the top players including

• Schneider Electric
• Siemens
• GE Ind.
• Eaton
• LS Cable
• UEC
• Huapeng Group
• C&S Electric
• DBTS Ind
• Godrej Busbar Systems
• Furukawa Electric
• Powell
• Honeywell
• Weton
• Somet
• ABB
• Dasheng Microgrid
• Huabei Changcheng
• WOER
• Lonsdaleite
• Amppelec
• Yuanda Electric
• Dynamic Electrical
• BYE
• Furutec Electrical
• Guangle Electric
• Baosheng
• Hanhe Cable
• PPB
• Larsen & Toubro

On the basis of product, this report displays the production, revenue, price, market share and growth rate of each type, primarily split into

• Air Splicing Bus Duct (BMC)
• Intensive Insulation Plug Bus Duct (CMC)
• Higher Strength Enclosed Bus Duct (CFW)

On the basis on the end users/applications, this report focuses on the status and outlook for major applications/end users, sales volume, market share and growth rate for each application, including

• Industrial Buildings
• Commercial Buildings
• Civil Buildings

If you have any special requirements, please let us know and we will offer you the report as you want.

Contents

United States Busway-Bus Duct Market Report 2018

1 BUSWAY-BUS DUCT OVERVIEW

1.1 Product Overview and Scope of Busway-Bus Duct
1.2 Classification of Busway-Bus Duct by Product Category
  1.2.1 United States Busway-Bus Duct Market Size (Sales Volume) Comparison by Type (2013-2025)
  1.2.2 United States Busway-Bus Duct Market Size (Sales Volume) Market Share by Type (Product Category) in 2017
  1.2.3 Air Splicing Bus Duct (BMC)
  1.2.4 Intensive Insulation Plug Bus Duct (CMC)
  1.2.5 Higher Strength Enclosed Bus Duct (CFW)
1.3 United States Busway-Bus Duct Market by Application/End Users
  1.3.1 United States Busway-Bus Duct Market Size (Consumption) and Market Share Comparison by Application (2013-2025)
  1.3.2 Industrial Buildings
  1.3.3 Commercial Buildings
  1.3.4 Civil Buildings
1.4 United States Busway-Bus Duct Market by Region
  1.4.1 United States Busway-Bus Duct Market Size (Value) Comparison by Region (2013-2025)
  1.4.2 The West Busway-Bus Duct Status and Prospect (2013-2025)
  1.4.3 Southwest Busway-Bus Duct Status and Prospect (2013-2025)
  1.4.4 The Middle Atlantic Busway-Bus Duct Status and Prospect (2013-2025)
  1.4.5 New England Busway-Bus Duct Status and Prospect (2013-2025)
  1.4.6 The South Busway-Bus Duct Status and Prospect (2013-2025)
  1.4.7 The Midwest Busway-Bus Duct Status and Prospect (2013-2025)
1.5 United States Market Size (Value and Volume) of Busway-Bus Duct (2013-2025)
  1.5.1 United States Busway-Bus Duct Sales and Growth Rate (2013-2025)
  1.5.2 United States Busway-Bus Duct Revenue and Growth Rate (2013-2025)

2 UNITED STATES BUSWAY-BUS DUCT MARKET COMPETITION BY PLAYERS/SUPPLIERS

2.1 United States Busway-Bus Duct Sales and Market Share of Key Players/Suppliers (2013-2018)
2.2 United States Busway-Bus Duct Revenue and Share by Players/Suppliers (2013-2018)
2.3 United States Busway-Bus Duct Average Price by Players/Suppliers (2013-2018)
2.4 United States Busway-Bus Duct Market Competitive Situation and Trends
  2.4.1 United States Busway-Bus Duct Market Concentration Rate
  2.4.2 United States Busway-Bus Duct Market Share of Top 3 and Top 5 Players/Suppliers
  2.4.3 Mergers & Acquisitions, Expansion in United States Market
2.5 United States Players/Suppliers Busway-Bus Duct Manufacturing Base Distribution, Sales Area, Product Type

3 UNITED STATES BUSWAY-BUS DUCT SALES (VOLUME) AND REVENUE (VALUE) BY REGION (2013-2018)

3.1 United States Busway-Bus Duct Sales and Market Share by Region (2013-2018)
3.2 United States Busway-Bus Duct Revenue and Market Share by Region (2013-2018)
3.3 United States Busway-Bus Duct Price by Region (2013-2018)

4 UNITED STATES BUSWAY-BUS DUCT SALES (VOLUME) AND REVENUE (VALUE) BY TYPE (PRODUCT CATEGORY) (2013-2018)

4.1 United States Busway-Bus Duct Sales and Market Share by Type (Product Category) (2013-2018)
4.2 United States Busway-Bus Duct Revenue and Market Share by Type (2013-2018)
4.3 United States Busway-Bus Duct Price by Type (2013-2018)
4.4 United States Busway-Bus Duct Sales Growth Rate by Type (2013-2018)

5 UNITED STATES BUSWAY-BUS DUCT SALES (VOLUME) BY APPLICATION (2013-2018)

5.1 United States Busway-Bus Duct Sales and Market Share by Application (2013-2018)
5.2 United States Busway-Bus Duct Sales Growth Rate by Application (2013-2018)
5.3 Market Drivers and Opportunities

6 UNITED STATES BUSWAY-BUS DUCT PLAYERS/SUPPLIERS PROFILES AND SALES DATA

6.1 Schneider Electric
  6.1.1 Company Basic Information, Manufacturing Base and Competitors
  6.1.2 Busway-Bus Duct Product Category, Application and Specification
    6.1.2.1 Product A
    6.1.2.2 Product B
  6.1.3 Schneider Electric Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.1.4 Main Business/Business Overview
6.2 Siemens
  6.2.2 Busway-Bus Duct Product Category, Application and Specification
    6.2.2.1 Product A
    6.2.2.2 Product B
  6.2.3 Siemens Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.2.4 Main Business/Business Overview
6.3 GE Ind.
  6.3.2 Busway-Bus Duct Product Category, Application and Specification
    6.3.2.1 Product A
    6.3.2.2 Product B
  6.3.3 GE Ind. Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.3.4 Main Business/Business Overview
6.4 Eaton
  6.4.2 Busway-Bus Duct Product Category, Application and Specification
    6.4.2.1 Product A
    6.4.2.2 Product B
  6.4.3 Eaton Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.4.4 Main Business/Business Overview
6.5 LS Cable
  6.5.2 Busway-Bus Duct Product Category, Application and Specification
    6.5.2.1 Product A
    6.5.2.2 Product B
  6.5.3 LS Cable Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.5.4 Main Business/Business Overview
6.6 UEC
  6.6.2 Busway-Bus Duct Product Category, Application and Specification
    6.6.2.1 Product A
    6.6.2.2 Product B
  6.6.3 UEC Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.6.4 Main Business/Business Overview
6.7 Huapeng Group
  6.7.2 Busway-Bus Duct Product Category, Application and Specification
    6.7.2.1 Product A
    6.7.2.2 Product B
  6.7.3 Huapeng Group Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.7.4 Main Business/Business Overview
6.8 C&S Electric
  6.8.2 Busway-Bus Duct Product Category, Application and Specification
    6.8.2.1 Product A
    6.8.2.2 Product B
  6.8.3 C&S Electric Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.8.4 Main Business/Business Overview
6.9 DBTS Ind
  6.9.2 Busway-Bus Duct Product Category, Application and Specification
    6.9.2.1 Product A
    6.9.2.2 Product B
  6.9.3 DBTS Ind Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.9.4 Main Business/Business Overview
6.10 Godrej Busbar Systems
  6.10.2 Busway-Bus Duct Product Category, Application and Specification
    6.10.2.1 Product A
    6.10.2.2 Product B
  6.10.3 Godrej Busbar Systems Busway-Bus Duct Sales, Revenue, Price and Gross Margin (2013-2018)
  6.10.4 Main Business/Business Overview
6.11 Furukawa Electric
6.12 Powell
6.13 Honeywell
6.14 Weton
6.15 Somet
6.16 ABB
6.17 Dasheng Microgrid
6.18 Huabei Changcheng
6.19 WOER
6.20 Lonsdaleite
6.21 Amppelec
6.22 Yuanda Electric
6.23 Dynamic Electrical
6.24 BYE
6.25 Furutec Electrical
6.26 Guangle Electric
6.27 Baosheng
6.28 Hanhe Cable
6.29 PPB
6.30 Larsen & Toubro

7 BUSWAY-BUS DUCT MANUFACTURING COST ANALYSIS

7.1 Busway-Bus Duct Key Raw Materials Analysis
  7.1.1 Key Raw Materials
  7.1.2 Price Trend of Key Raw Materials
  7.1.3 Key Suppliers of Raw Materials
  7.1.4 Market Concentration Rate of Raw Materials
7.2 Proportion of Manufacturing Cost Structure
  7.2.1 Raw Materials
  7.2.2 Labor Cost
  7.2.3 Manufacturing Expenses
7.3 Manufacturing Process Analysis of Busway-Bus Duct

8 INDUSTRIAL CHAIN, SOURCING STRATEGY AND DOWNSTREAM BUYERS

8.1 Busway-Bus Duct Industrial Chain Analysis
8.2 Upstream Raw Materials Sourcing
8.3 Raw Materials Sources of Busway-Bus Duct Major Manufacturers in 2017
8.4 Downstream Buyers

9 MARKETING STRATEGY ANALYSIS, DISTRIBUTORS/TRADERS

9.1 Marketing Channel
  9.1.1 Direct Marketing
  9.1.2 Indirect Marketing
  9.1.3 Marketing Channel Development Trend
9.2 Market Positioning
  9.2.1 Pricing Strategy
  9.2.2 Brand Strategy
  9.2.3 Target Client
9.3 Distributors/Traders List

10 MARKET EFFECT FACTORS ANALYSIS

10.1 Technology Progress/Risk
  10.1.1 Substitutes Threat
  10.1.2 Technology Progress in Related Industry
10.2 Consumer Needs/Customer Preference Change
10.3 Economic/Political Environmental Change

11 UNITED STATES BUSWAY-BUS DUCT MARKET SIZE (VALUE AND VOLUME) FORECAST (2018-2025)

11.1 United States Busway-Bus Duct Sales Volume, Revenue Forecast (2018-2025)
11.2 United States Busway-Bus Duct Sales Volume Forecast by Type (2018-2025)
11.3 United States Busway-Bus Duct Sales Volume Forecast by Application (2018-2025)
11.4 United States Busway-Bus Duct Sales Volume Forecast by Region (2018-2025)

12 RESEARCH FINDINGS AND CONCLUSION

13 APPENDIX

13.1 Methodology/Research Approach
  13.1.1 Research Programs/Design
  13.1.2 Market Size Estimation
  13.1.3 Market Breakdown and Data Triangulation
13.2 Data Source
  13.2.1 Secondary Sources
  13.2.2 Primary Sources
13.3 Disclaimer

The report requires updating with new data and is sent in 2-3 business days after order is placed.

List Of Tables

LIST OF TABLES AND FIGURES

Figure Product Picture of Busway-Bus Duct
Figure United States Busway-Bus Duct Market Size (K Units) by Type (2013-2025)
Figure United States Busway-Bus Duct Sales Volume Market Share by Type (Product Category) in 2017
Figure Air Splicing Bus Duct (BMC) Product Picture
Figure Intensive Insulation Plug Bus Duct (CMC) Product Picture
Figure Higher Strength Enclosed Bus Duct (CFW) Product Picture
Figure United States Busway-Bus Duct Market Size (K Units) by Application (2013-2025)
Figure United States Sales Market Share of Busway-Bus Duct by Application in 2017
Figure Industrial Buildings Examples
Table Key Downstream Customer in Industrial Buildings
Figure Commercial Buildings Examples
Table Key Downstream Customer in Commercial Buildings
Figure Civil Buildings Examples
Table Key Downstream Customer in Civil Buildings
Figure United States Busway-Bus Duct Market Size (Million USD) by Region (2013-2025)
Figure The West Busway-Bus Duct Revenue (Million USD) and Growth Rate (2013-2025)
Figure Southwest Busway-Bus Duct Revenue (Million USD) and Growth Rate (2013-2025)
Figure The Middle Atlantic Busway-Bus Duct Revenue (Million USD) and Growth Rate (2013-2025)
Figure New England Busway-Bus Duct Revenue (Million USD) and Growth Rate (2013-2025)
Figure The South of US Busway-Bus Duct Revenue (Million USD) and Growth Rate (2013-2025)
Figure The Midwest Busway-Bus Duct Revenue (Million USD) and Growth Rate (2013-2025)
Figure United States Busway-Bus Duct Sales (K Units) and Growth Rate (2013-2025)
Figure United States Busway-Bus Duct Revenue (Million USD) and Growth Rate (2013-2025)
Figure United States Busway-Bus Duct Market Major Players Product Sales Volume (K Units) (2013-2018)
Table United States Busway-Bus Duct Sales (K Units) of Key Players/Suppliers (2013-2018)
Table United States Busway-Bus Duct Sales Share by Players/Suppliers (2013-2018)
Figure 2017 United States Busway-Bus Duct Sales Share by Players/Suppliers
Figure 2017 United States Busway-Bus Duct Sales Share by Players/Suppliers
Figure United States Busway-Bus Duct Market Major Players Product Revenue (Million USD) (2013-2018)
Table United States Busway-Bus Duct Revenue (Million USD) by Players/Suppliers (2013-2018)
Table United States Busway-Bus Duct Revenue Share by Players/Suppliers (2013-2018)
Figure 2017 United States Busway-Bus Duct Revenue Share by Players/Suppliers
Figure 2017 United States Busway-Bus Duct Revenue Share by Players/Suppliers
Table United States Market Busway-Bus Duct Average Price (USD/Unit) of Key Players/Suppliers (2013-2018)
Figure United States Market Busway-Bus Duct Average Price (USD/Unit) of Key Players/Suppliers in 2017
Figure United States Busway-Bus Duct Market Share of Top 3 Players/Suppliers
Figure United States Busway-Bus Duct Market Share of Top 5 Players/Suppliers
Table United States Players/Suppliers Busway-Bus Duct Manufacturing Base Distribution and Sales Area
Table United States Players/Suppliers Busway-Bus Duct Product Category
Table United States Busway-Bus Duct Sales (K Units) by Region (2013-2018)
Table United States Busway-Bus Duct Sales Share by Region (2013-2018)
Figure United States Busway-Bus Duct Sales Share by Region (2013-2018)
Figure United States Busway-Bus Duct Sales Market Share by Region in 2017
Table United States Busway-Bus Duct Revenue (Million USD) and Market Share by Region (2013-2018)
Table United States Busway-Bus Duct Revenue Share by Region (2013-2018)
Figure United States Busway-Bus Duct Revenue Market Share by Region (2013-2018)
Figure United States Busway-Bus Duct Revenue Market Share by Region in 2017
Table United States Busway-Bus Duct Price (USD/Unit) by Region (2013-2018)
Table United States Busway-Bus Duct Sales (K Units) by Type (2013-2018)
Table United States Busway-Bus Duct Sales Share by Type (2013-2018)
Figure United States Busway-Bus Duct Sales Share by Type (2013-2018)
Figure United States Busway-Bus Duct Sales Market Share by Type in 2017
Table United States Busway-Bus Duct Revenue (Million USD) and Market Share by Type (2013-2018)
Table United States Busway-Bus Duct Revenue Share by Type (2013-2018)
Figure Revenue Market Share of Busway-Bus Duct by Type (2013-2018)
Figure Revenue Market Share of Busway-Bus Duct by Type in 2017
Table United States Busway-Bus Duct Price (USD/Unit) by Types (2013-2018)
Figure United States Busway-Bus Duct Sales Growth Rate by Type (2013-2018)
Table United States Busway-Bus Duct Sales (K Units) by Application (2013-2018)
Table United States Busway-Bus Duct Sales Market Share by Application (2013-2018)
Figure United States Busway-Bus Duct Sales Market Share by Application (2013-2018)
Figure United States Busway-Bus Duct Sales Market Share by Application in 2017
Table United States Busway-Bus Duct Sales Growth Rate by Application (2013-2018)
Figure United States Busway-Bus Duct Sales Growth Rate by Application (2013-2018)
Table Schneider Electric Basic Information List
Table Schneider Electric Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure Schneider Electric Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure Schneider Electric Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure Schneider Electric Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table Siemens Basic Information List
Table Siemens Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure Siemens Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure Siemens Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure Siemens Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table GE Ind. Basic Information List
Table GE Ind. Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure GE Ind. Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure GE Ind. Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure GE Ind. Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table Eaton Basic Information List
Table Eaton Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure Eaton Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure Eaton Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure Eaton Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table LS Cable Basic Information List
Table LS Cable Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure LS Cable Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure LS Cable Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure LS Cable Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table UEC Basic Information List
Table UEC Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure UEC Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure UEC Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure UEC Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table Huapeng Group Basic Information List
Table Huapeng Group Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure Huapeng Group Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure Huapeng Group Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure Huapeng Group Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table C&S Electric Basic Information List
Table C&S Electric Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure C&S Electric Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure C&S Electric Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure C&S Electric Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table DBTS Ind Basic Information List
Table DBTS Ind Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure DBTS Ind Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure DBTS Ind Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure DBTS Ind Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table Godrej Busbar Systems Basic Information List
Table Godrej Busbar Systems Busway-Bus Duct Sales (K Units), Revenue (Million USD), Price (USD/Unit) and Gross Margin (2013-2018)
Figure Godrej Busbar Systems Busway-Bus Duct Sales Growth Rate (2013-2018)
Figure Godrej Busbar Systems Busway-Bus Duct Sales Market Share in United States (2013-2018)
Figure Godrej Busbar Systems Busway-Bus Duct Revenue Market Share in United States (2013-2018)
Table Furukawa Electric Basic Information List
Table Powell Basic Information List
Table Honeywell Basic Information List
Table Weton Basic Information List
Table Somet Basic Information List
Table ABB Basic Information List
Table Dasheng Microgrid Basic Information List
Table Huabei Changcheng Basic Information List
Table WOER Basic Information List
Table Lonsdaleite Basic Information List
Table Amppelec Basic Information List
Table Yuanda Electric Basic Information List
Table Dynamic Electrical Basic Information List
Table BYE Basic Information List
Table Furutec Electrical Basic Information List
Table Guangle Electric Basic Information List
Table Baosheng Basic Information List
Table Hanhe Cable Basic Information List
Table PPB Basic Information List
Table Larsen & Toubro Basic Information List
Table Production Base and Market Concentration Rate of Raw Material
Figure Price Trend of Key Raw Materials
Table Key Suppliers of Raw Materials
Figure Manufacturing Cost Structure of Busway-Bus Duct
Figure Manufacturing Process Analysis of Busway-Bus Duct
Figure Busway-Bus Duct Industrial Chain Analysis
Table Raw Materials Sources of Busway-Bus Duct Major Players/Suppliers in 2017
Table Major Buyers of Busway-Bus Duct
Table Distributors/Traders List
Figure United States Busway-Bus Duct Sales Volume (K Units) and Growth Rate Forecast (2018-2025)
Figure United States Busway-Bus Duct Revenue (Million USD) and Growth Rate Forecast (2018-2025)
Figure United States Busway-Bus Duct Price (USD/Unit) Trend Forecast (2018-2025)
Table United States Busway-Bus Duct Sales Volume (K Units) Forecast by Type (2018-2025)
Figure United States Busway-Bus Duct Sales Volume (K Units) Forecast by Type (2018-2025)
Figure United States Busway-Bus Duct Sales Volume (K Units) Forecast by Type in 2025
Table United States Busway-Bus Duct Sales Volume (K Units) Forecast by Application (2018-2025)
Figure United States Busway-Bus Duct Sales Volume (K Units) Forecast by Application (2018-2025)
Figure United States Busway-Bus Duct Sales Volume (K Units) Forecast by Application in 2025
Table United States Busway-Bus Duct Sales Volume (K Units) Forecast by Region (2018-2025)
Table United States Busway-Bus Duct Sales Volume Share Forecast by Region (2018-2025)
Figure United States Busway-Bus Duct Sales Volume Share Forecast by Region (2018-2025)
Figure United States Busway-Bus Duct Sales Volume Share Forecast by Region in 2025
Table Research Programs/Design for This Report
Figure Bottom-up and Top-down Approaches for This Report
Figure Data Triangulation
Table Key Data Information from Secondary Sources
Table Key Data Information from Primary Sources