Cita APA (7a ed.)

Johnson, R. (1930). The Art of retouching photografic negatives and practical directions how to finish and color photographic enlargements, etc (12th ed. rev and enlarged.). American Photographic Publishing Co.

Cita Chicago Style (17a ed.)

Johnson, Robert. The Art of Retouching Photografic Negatives and Practical Directions How to Finish and Color Photographic Enlargements, Etc. 12th ed. rev and enlarged. Boston: American Photographic Publishing Co, 1930.

Cita MLA (9a ed.)

Johnson, Robert. The Art of Retouching Photografic Negatives and Practical Directions How to Finish and Color Photographic Enlargements, Etc. 12th ed. rev and enlarged. American Photographic Publishing Co, 1930.