References for the Free Molecular Flow Interface
1. F. Celestini and F. Mortessagne, “Cosine Law at the Atomic Scale: Toward Realistic Simulations of Knudsen Diffusion”, Phys. Rev. E, vol. 77, 021202, 2008.
2. J.M. Lafferty, Foundations of Vacuum Science and Technology, Wiley Interscience, 1998.
3. J.F. O’Hanlon, A User’s Guide to Vacuum Technology, Wiley Interscience, 2003.