Celebratio Mathematica

A. Dold, S. Mac Lane, and U. Ober­st: “Pro­ject­ive classes and acyc­lic mod­els,” pp. 78–​91 in Re­ports of the Mid­w­est cat­egory sem­in­ar. Lec­ture Notes in Math­em­at­ics 47. Spring­er (Ber­lin), 1967. MR 0236245 incollection

J. Bén­abou, R. Dav­is, A. Dold, J. R. Is­bell, S. MacLane, U. Ober­st, and J.-E. Roos: Re­ports of the Mid­w­est cat­egory sem­in­ar. Lec­ture Notes in Math­em­at­ics 47. Spring­er (New York), 1967. MR 0220788 Zbl 0165.​33001 book