APA (7th ed.) Citation

Lopker. (2000). Pictures of Personality Guide to the four human natures (1.). Typology.

Chicago Style (17th ed.) Citation

Lopker. Pictures of Personality Guide to the Four Human Natures. 1. London: Typology, 2000.

MLA (9th ed.) Citation

Lopker. Pictures of Personality Guide to the Four Human Natures. 1. Typology, 2000.

Warning: These citations may not always be 100% accurate.