APA-ийн эшлэл(7 дахь хэвлэлт)

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

Чикаго-гийн эшлэл (17 дахь хэвлэлт)

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

MLA -ийн эшлэл (9 дэх хэвлэлт)

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