Paul Anh McEldowney, Bolzano against Kant's Pure Intuition.- Jeremy Shipley, Poincare on the Foundation of Geometry in Understanding.- Fabio Lampert, Natural Deduction for Diagonal Operators.- Valerie Allen, What is a Symbol?- Polar Ordinates in Bernoulli and L'Hopital.- Magic Squares of Subtraction of Adam Adamandy Kochanski.- Euler's E228: Primality Testing and Factoring via Sums of Squares.- Eisso J. Atzema, "A Most Elegant Property": On the Early History of Lexell's Theorem.- Amy Ackerberg-Hastings, The Misnamings of Playfair's Axiom.- Joel Silverberg, Napier, Toporley, Menelaus, and Ptolemy: Delambre and De Morgan's on Seventeenth-Century Restructuring of Spherical Trigonometry.- Mariya Boyko, The Reception of American Mathematics Education in Soviet Pedagogical Journals of the 1960s and 1970s.- Craig Fraser, Mathematics in Library Subject Classification Systems.- Roger Godard, The Convolution as a Mathematical Object.- George Heine, Sundials - Une Promenade Parisienne(A Math Walk in Paris).