Celebratio Mathematica

A. S. Schwarz and Yu. S. Ty­up­kin: “Grand uni­fic­a­tion, strings, and mir­ror particles,” pp. 279–​289 in Group the­or­et­ic­al meth­ods in phys­ics (Zvenig­orod, USSR, 24–26 Novem­ber 1982), vol. 2. Edi­ted by M. A. Markov, V. I. Man’ko, and A. E. Shabad. Har­wood Aca­dem­ic (Chur, Switzer­land), 1985. MR 989351 incollection