%0 Journal Article %T Approximations and locally free modules %A Alexander Slavik %A Jan Trlifaj %J Mathematics %D 2012 %I arXiv %R 10.1112/blms/bdt069 %X For any set of modules S, we prove the existence of precovers (right approximations) for all classes of modules of bounded C-resolution dimension, where C is the class of all S-filtered modules. In contrast, we use infinite dimensional tilting theory to show that the class of all locally free modules induced by a non-sum-pure-split tilting module is not precovering. Consequently, the class of all locally Baer modules is not precovering for any countable hereditary artin algebra of infinite representation type. %U http://arxiv.org/abs/1210.7097v1