APA (7th ed.) Citation

Hoffer, O. (1980). Imitation gemstones: Random personal reminiscences. O. Hoffer.

Chicago Style (17th ed.) Citation

Hoffer, Otto. Imitation Gemstones: Random Personal Reminiscences. [Providence, R.I.?]: O. Hoffer, 1980.

MLA (9th ed.) Citation

Hoffer, Otto. Imitation Gemstones: Random Personal Reminiscences. O. Hoffer, 1980.

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