Cita APA (7th ed.)
Johnson, F., & Hammar, A. (1910). The Grape-Root-Worm.
Cita Chicago (17th ed.)
Johnson, Fred, i A.G Hammar. The Grape-Root-Worm. Washington, 1910.
Cita MLA (9th ed.)
Johnson, Fred, i A.G Hammar. The Grape-Root-Worm. 1910.
Atenció: Aquestes cites poden no estar 100% correctes.