APA (7th ed.) Citation

Webster, R. (1967). The Gemmologists' compendium / by R. Webster (4th ed.). N.A.G..

Chicago Style (17th ed.) Citation

Webster, R. The Gemmologists' Compendium / by R. Webster. 4th ed. London: N.A.G., 1967.

MLA (9th ed.) Citation

Webster, R. The Gemmologists' Compendium / by R. Webster. 4th ed. N.A.G., 1967.

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