Beringer, C., & Beringer, J. J. (2006). A Text-book of Assaying: For the Use of Those Connected with Mines. Project Gutenberg.
Chicago Style (17th ed.) CitationBeringer, C., and J. J. Beringer. A Text-book of Assaying: For the Use of Those Connected with Mines. Project Gutenberg, 2006.
MLA (9th ed.) CitationBeringer, C., and J. J. Beringer. A Text-book of Assaying: For the Use of Those Connected with Mines. Project Gutenberg, 2006.
Warning: These citations may not always be 100% accurate.