United States. Postmaster General. (1922). Ascertainment of cost of handling and transporting several classes of mail matter and conducting special services for purpose of making report to Joint Commission of Congress on Postal Service: Instruction letter D-c (series D); expenditures, group "C," 1st-class post offices. [publisher not identified].
Chicago Style (17th ed.) CitationUnited States. Postmaster General. Ascertainment of Cost of Handling and Transporting Several Classes of Mail Matter and Conducting Special Services for Purpose of Making Report to Joint Commission of Congress on Postal Service: Instruction Letter D-c (series D); Expenditures, Group "C," 1st-class Post Offices. Washington: [publisher not identified], 1922.
MLA (9th ed.) CitationUnited States. Postmaster General. Ascertainment of Cost of Handling and Transporting Several Classes of Mail Matter and Conducting Special Services for Purpose of Making Report to Joint Commission of Congress on Postal Service: Instruction Letter D-c (series D); Expenditures, Group "C," 1st-class Post Offices. [publisher not identified], 1922.