Boegel, H. (1971). A collector's guide to minerals and gemstones. Thames and Hudson.
Chicagoスタイル(17版)引用形式Boegel, Hellmuth. A Collector's Guide to Minerals and Gemstones. London, England, United Kingdom: Thames and Hudson, 1971.
MLA(9版)引用形式Boegel, Hellmuth. A Collector's Guide to Minerals and Gemstones. Thames and Hudson, 1971.
警告: この引用は必ずしも正確ではありません.