My Erdös number calculation was done via MathSciNet
P. Erdös and A. Sharma,
On Tchebycheff quadrature.
Canad. J. Math. 17, 652--658 (1965).
K.E. Atkinson and A. Sharma,
A partial characterization of poised Hermite-Birkhoff interpolation problems.
SIAM J. Numer. Anal., 6, 230--235 (1969).
K.E. Atkinson, I.G. Graham and I.H. Sloan,
Piecewise continuous collocation for integral equations.
SIAM J. Numer. Anal, 20, 172--186 (1983).