We the underwritten members of the Royal Society of London, and of the Royal Academy of Sciences of Paris: do hereby testifie that Mr de la Chappelle, author of the book entitled Institutions of geometry [(Chapelle 46)], well deserves to be elected into the Royal Society, both on account of the works he has published already, and on account of those others which may reasonably be expected from his continual and diligent application, to philosophy, mathematicks, and natural knowledge. In wittness whereof we have signed the present certificate, at Paris this first day of March 1747 (N[ew] S[tyle]). Du Hamel de Monceau, de Fouchy, Hellot, Clairaut, Morand, Le Monier [Le Monnier], de Mairan (RS, EC/1747/07).
London March 12 1746 O[ld] S[tyle]. I also well knowing Mr De la Chappelle, am glad of this oppertunity of adding my name to those of the worthy Gentlemen who have Signed above. M. Folkes (RS, EC/1747/07). Jean-Baptiste de la Chapelle (1710 ?-1792) est membre de la Royal Society le (29) 18 juin 1747 (RS, EC/1747/07).
Courcelle (Olivier), « 1 mars 1747 (1) : Clairaut à la Royal Society », Chronologie de la vie de Clairaut (1713-1765) [En ligne], http://www.clairaut.com/n1mars1747po1pf.html [Notice publiée le 10 mai 2010].
I also well knowing Mr De la Chappelle, am glad of this oppertunity of adding my name to those of the worthy Gentlemen who have Signed above. M. Folkes (RS, EC/1747/07). Jean-Baptiste de la Chapelle (1710 ?-1792) est membre de la Royal Society le (29) 18 juin 1747 (RS, EC/1747/07).