Published: Aug 18, 2016 by The PISM Authors
Please acknowledge the funding that makes PISM possible, and which supports its continued maintenance and technical support. Include the sentence “Development of PISM is supported by NASA grants NNX13AM16G and NNX13AK27G.” in the Acknowledgments part of your paper.
If authors do this consistently then it will help to ensure continued funding of PISM!
For specific suggestions on how to cite the design or justification of PISM see this page.