APA (7th ed.) Citation

Helden, A. C. v., & Gent, R. H. v. (1999). The lens production by Christiaan and Constantijn Huygens.

Chicago Style (17th ed.) Citation

Helden, Anne C. van, and Robert H. van Gent. The Lens Production by Christiaan and Constantijn Huygens. 1999.

MLA (9th ed.) Citation

Helden, Anne C. van, and Robert H. van Gent. The Lens Production by Christiaan and Constantijn Huygens. 1999.

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