I am trying to solve a weighted set cover problem where the number of selected subsets is limited by a constant $k$. Assuming this is a pretty straight-forward variation of weighted set cover I ended up quite confused with only one, also rather recent paper by Golab et al. .
Am I missing something here?
 Golab, Korn, Li, Saha and Srivastava, Size-constrained weighted set cover. In _Proceedings of 31st International Conference on Data Engineering (ICDE), pp. 879–890. IEEE, 2015. IEEE Digital Library; author PDF.