@software{nathaniel_j_smith_2015_20981, author = {Nathaniel J. Smith and Christian Hudon and broessli and Skipper Seabold and Cameron Davidson-Pilon}, title = {patsy: v0.4.0}, month = jul, year = 2015, publisher = {Zenodo}, version = {v0.4.0}, doi = {10.5281/zenodo.20981}, url = {https://doi.org/10.5281/zenodo.20981} }