Cita APA (7th ed.)
Johnson, L. G. Biology. Wm.C. Brown.
Cita Chicago (17th ed.)
Johnson, Leland G. Biology. Iowa: Wm.C. Brown.
Cita MLA (9th ed.)
Johnson, Leland G. Biology. Wm.C. Brown.
Atenció: Aquestes cites poden no estar 100% correctes.