Stichting Mathematisch Centrum
Stichting Mathematisch Centrum. Zuivere Wiskunde

Baayen, P.C, Kuyk, W, & Maurice, M.A. (1962). On the orbits of the hat-function and on countable maximal commutative semigroups of continuous mappings of the unit interval into itself. Stichting Mathematisch Centrum. Zuivere Wiskunde. Stichting Mathematisch Centrum.