Harasim P., Valdman Jan :  Verification of functional a posteriori error estimates for obstacle problem in 2D , Kybernetika vol.50, 6 (2014), p. 978-1002 [2014] Download DOI: 10.14736/kyb-2014-6-0978

Harasim P., Valdman Jan :  Verification of functional a posteriori error estimates for obstacle problem in 1D , Kybernetika vol.49, 5 (2013), p. 738-754 [2013] Download