APA (7th ed.) Citation

Orígenes. (1966). On first principles. Harper & Row.

Chicago Style (17th ed.) Citation

Orígenes. On First Principles. Nueva York: Harper & Row, 1966.

MLA (9th ed.) Citation

Orígenes. On First Principles. Harper & Row, 1966.

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