Cita APA (7th ed.)

Hopkins , W. C., & Williams, D. L. (1968). Converting factors for Southern pine products. State University.

Cita Chicago (17th ed.)

Hopkins , William C., i David L. Williams. Converting Factors for Southern Pine Products. Louisiana: State University, 1968.

Cita MLA (9th ed.)

Hopkins , William C., i David L. Williams. Converting Factors for Southern Pine Products. State University, 1968.