Natuurkundige verhandelingen van Petrus Camper over den orang outang; en eenige andere aap-soorten. Over den rhinoceros met den dubbelen horen; en over het rendier.

Having dissected five orang-outang cadavers, Camper showed that the Bornean orang-outang was a previously undescribed species, and showed that the structure of its vocal organs did not permit speech. Digital facsimile from Google Books at this link.