Unofficial history of a joint work with Dieter Happel and of two unexpected quotations
D'Este, G.
Abstract. This survey contains a recollection of results, problems and conversations which go back to the early years of Representation Theory and Tilting Theory.
Dedicated to the memory of Dieter Happel
Rend. Mat. Appl. (7) 35 (2014) 115-130; pdf