Barry, Paul (2013) A Note on a Family of Generalized Pascal Matrices Defined by Riordan Arrays. Journal of Integer Sequences, 16. ISSN 1530-7638
O'Raifeartaigh, Cormac (2013) The contribution of VM Slipher to the discovery of the expanding universe. In: Origins of the Expanding Universe 1912-1932. Astronomical Society of the Pacific. ISBN 978-1-58381-826-8