(1961). Government Patent Policy. hearings before the United States Senate Committee on the Judiciary, Subcommittee on Patents, Trademarks, and Copyrights, Eighty-Seventh Congress, first session, on Apr. 18-21, 1961. [electronic resource]: Part 1.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিGovernment Patent Policy. Hearings Before the United States Senate Committee on the Judiciary, Subcommittee on Patents, Trademarks, and Copyrights, Eighty-Seventh Congress, First Session, on Apr. 18-21, 1961. [electronic Resource]: Part 1. 1961.
M.L.A (9 ম সংস্করণ) উদ্ধৃতিGovernment Patent Policy. Hearings Before the United States Senate Committee on the Judiciary, Subcommittee on Patents, Trademarks, and Copyrights, Eighty-Seventh Congress, First Session, on Apr. 18-21, 1961. [electronic Resource]: Part 1. 1961.