Jean-Paul Sartre
Critique de la raison dialectique. 
Paris: Editions Gallimard, 1974/1985. Bibliothèque des Idees/Bibliothèque de Philosophie. 2070705252 (second volume only) Second volume was edited, with notes and a glossary, by Arlette Elkaïm-Sartre. 755/469 pages.
First volume is softcover, measuring approximately 5.75" x 9", showing light shelfwear, with sound binding, clean and bright interior; second volume is hardcover, measuring approximately 5.75" x 9", is in fine condition. Dust jacket displays light shelfwear, with uneven darkening of edges of front panel. 
Philosophical treatise, originally published in 1960, with the subtitle "Theorie des ensembles pratiques" (preceded by the 1957 text "Questions de methode"). An unfinished second volume, "L'intelligibilité de l'Histoire," was posthumously published in 1985.
This work elaborates on the existentialist Marxism Sartre first expounded in his essay "Search for a Method" (1957).