Answer
Denis Diderot and Jean Le Rond d'Alembert co-edited the Encyclopédie, a French Enlightenment reference work published between 1751 and 1772. The Encyclopédie was a massive undertaking, and Diderot and d'Alembert worked tirelessly to produce it. They faced censorship and opposition from the authorities, but they persevered and the Encyclopédie became a landmark publication.