Celebratio Mathematica

E. M. Stein and A. Zyg­mund: “Smooth­ness and dif­fer­en­ti­ab­il­ity of func­tions,” Ann. Univ. Sci. Bud­apest, Eötvös Sect. Math. 3–4 (1960–1961), pp. 295–​307. MR 0132135 Zbl 0104.​04803 article

E. M. Stein and A. Zyg­mund: “On the dif­fer­en­ti­ab­il­ity of func­tions,” Stu­dia Math. 23 : 3 (1963–1964), pp. 247–​283. Ded­ic­ated to E. Hille on the oc­ca­sion of his 70th birth­day. MR 0158955 Zbl 0122.​30203 article

E. M. Stein and A. Zyg­mund: “On the frac­tion­al dif­fer­en­ti­ab­il­ity of func­tions,” Proc. Lon­don Math. Soc. (3) 14A : 1 (1965), pp. 249–​264. To J. E. Lit­tle­wood on his 80th birth­day. MR 0177076 Zbl 0154.​05501 article

E. M. Stein and A. Zyg­mund: “Bounded­ness of trans­la­tion in­vari­ant op­er­at­ors on Hölder spaces and \( L^p \)-spaces,” Ann. Math. (2) 85 : 2 (March 1967), pp. 337–​349. MR 0215121 Zbl 0172.​40102 article

E. M. Stein and A. Zyg­mund: “On the bound­ary be­ha­vi­or of har­mon­ic func­tions,” pp. 127–​141 in Or­tho­gon­al ex­pan­sions and their con­tinu­ous ana­logues (Ed­wards­ville, IL, 27–29 April 1967). Edi­ted by D. T. Haimo. South­ern Illinois Uni­versity Press (Car­bondale, IL), 1968. MR 0234001 Zbl 0157.​42501 incollection

C. Fef­fer­man, J.-P. Ka­hane, and E. M. Stein: “O dorob­ku naukow­ym Ant­oniego Zyg­munda” [The sci­entif­ic achieve­ments of Ant­oni Zyg­mund], Wia­dom. Mat. (2) 19 : 2 (1976), pp. 91–​126. MR 0433115 article

A. P. Calder­ón and E. M. Stein: “Ant­oni Zyg­mund: 1900–1992,” No­tices Am. Math. Soc. 39 : 8 (1992), pp. 848–​849. MR 1182969 Zbl 1194.​01074 article