Although it appears in at least one bibliography of the better-known Henri Lefebvre, Les unités perdues, translated as The Missing Pieces, is actually by a different author, born in 1959. It’s an interesting book on abandoned, lost, destroyed, forgotten and unfinished works, and a short excerpt is available on the Berfrois website.

Update September 2026: unfortunately, though perhaps fittingly, the excerpt has disappeared with the demise of Berfrois. I briefly write about the confusion of this Henri Lefebvre with the more famous Marxist in one of my ‘Sunday History‘ pieces.