@article{jameson,
author = {Jameson,G. J. O.},
title = {A simple proof of {S}tirling's formula for the {G}amma function},
journal = {The Mathematical Gazette},
volume = {99},
issue = {544},
month = {3},
month = {3},
year = {2015},
issn = {2056-6328},
pages = {68--74},
numpages = {7},
doi = {10.1017/mag.2014.9},
URL = {http://journals.cambridge.org/article_S0025557215007676},
}

@book{berndt,
  title={Rudiments of the Theory of the Gamma Function},
  author={Berndt, B.C.},
  url={http://www.math.uiuc.edu/~berndt/theory_gamma_function.pdf},
  year={1976},
  publisher={University of Chicago}
}

@book{erdelyi,
  title={Asymptotic Expansions},
  author={Erd\'{e}lyi, A.},
  year={1956},
  publisher={Dover Publications}
}
