His administrative experience formed the basis of his principal work, the Coustumes de Beauvoisis of 1283, which was first printed in 1690. Even though barely noticed in its own time, it was later regarded as one of the best works bearing on old French customary law, and was frequently referred to with high admiration by Montesquieu, who called him la lumière de son temps ("the light of his time").
References
Montazel, Laurence (2001). "Philippe de Beaumanoir". In Michael Stolleis (ed.). Juristen: ein biographisches Lexikon; von der Antike bis zum 20. Jahrhundert (in German) (2nd ed.). München: Beck. p. 71. ISBN3-406-45957-9.
Akehurst, F. R. P. (March 1992). The Coutumes de Beauvaisis of Philippe de Beaumanoir. University of Pennsylvania Press. p. 749. ISBN0-8122-3105-8.
Heller, Sarah-Grace; Reichert, Michelle (November 2001). Essays on the Poetic and Legal Writings of Philippe De Remy and His Son Phiilippe De Beaumanoir of Thirteenth-Century France. Edwin Mellen Press. p. 304. ISBN0-7734-7383-1.