If you use SNCosmo for work presented in a publication, you can include a citation to the code. See http://dx.doi.org/10.5281/zenodo.11938 for citation styles.
A BibTeX entry for LaTeX users is:
@article{Barbary:11938,
author = "Barbary, Kyle",
title = "{sncosmo v0.4.2}",
month = "Apr",
year = "2014",
doi = "{10.5281/zenodo.11938}",
url = "{http://dx.doi.org/10.5281/zenodo.11938}",
}