Linq join with two coloumns

Please refer following threads:

A beginner's LINQ tutorial that walks you through mapping your SQL Server database tables and relationships to objects, and how to retrieve that data via simple LINQ queries:
A LINQ Tutorial: Mapping Tables to Objects[^]
Using LINQ Queries[^]
Dynamic Table Mapping for Linq-to-SQL[^]
LINQ to SQL: Advanced Concepts and Features[^]
How to succesfully join two in-memory linq collections?[^]
How to do joins in LINQ on multiple fields in single join[^]