A. H. Erhardt:
Calderón-Zygmund theory for parabolic obstacle problems with nonstandard growth
Adv. Nonlinear Anal. Vol. 3, N. 1, p. 15-44, 2014

A. H. Erhardt:
Hölder estimates for parabolic obstacle problems
Ann. Mat. Pura Appl. (4) Vol. 194, N. 3, p. 645-671 , 2015

A. H. Erhardt:
Existence of solutions to parabolic problems with nonstandard growth and irregular obstacles
Adv. Differential Equations Vol. 21, N. 5-6, p. 463504, 2016

A. H. Erhardt:
Higher integrability for solutions to parabolic problems with irregular obstacles and nonstandard growth
J. Math. Anal. Appl. Vol. 435, N. 2, p. 17721803, 2016