1. V. V. Zhikov, “On Lavrentiev’s Phenomenon,” Russ. J. Math. Phys. 3(2), 249–269 (1995).
2. V. V. Zhikov, “On Some Variational Problems,” Russ. J. Math. Phys. 5(1), 105–116 (1997).
3. X. Fan and D. Zhao, “A Class of De Giorgi Type and Hölder Continuity,” Nonlinear Anal., Theory Methods Appl. 36(3), 295–318 (1999).
4. Yu. A. Alkhutov, “The Harnack Inequality and the Hölder Property of Solutions of Nonlinear Elliptic Equations with a Nonstandard Growth Condition,” Diff. Uravn. 33(12), 1651–1660 (1997) [Diff. Eqns. 33, 1653–1663 (1997)].
5. O. V. Krasheninnikova, “Continuity at a Point for Solutions to Elliptic Equations with a Nonstandard Growth Condition,” Tr. Mat. Inst. im. V.A Steklova, Ross. Akad. Nauk 236, 204–211 (2002) [Proc. Steklov Inst. Math. 236, 193–200 (2002)].