@article {1708.05370, archivePrefix = {arXiv}, eprint = {1708.05370}, primaryClass = {cond-mat.stat-mech}, author = {Nitzan Razin and Raphael Voituriez and Jens Elgeti and Nir S. Gov}, title = {Forces in inhomogeneous open active-particle systems}, year = {2017}, url = {http://arxiv.org/abs/1708.05370} }