Ahmed, Z. "Definitely An Integral." Amer. Math. Monthly109, 670-671, 2002.Borwein, J.; Bailey, D.; and Girgensohn,
R. "Ahmed's Integral Problem." §1.6 in Experimentation
in Mathematics: Computational Paths to Discovery. Wellesley, MA: A K Peters,
pp. 17-20, 2004.Sloane, N. J. A. Sequences A096615,
A098459, and A102521
in "The On-Line Encyclopedia of Integer Sequences."