The billiard problem
Gander, Walter
The billiard problem - 825-830 - 1992 Vol. 23, no. 6, nov.-dec. = INTERNATIONAL JOURNAL OF MATHEMATICAL EDUCATION IN SCIENCE AND TECHNOLOGY
ALGEBRA ENSEÑANZA GEOMETRIA MATEMATICA SOFTWARE EDUCATIVO
The billiard problem - 825-830 - 1992 Vol. 23, no. 6, nov.-dec. = INTERNATIONAL JOURNAL OF MATHEMATICAL EDUCATION IN SCIENCE AND TECHNOLOGY
ALGEBRA ENSEÑANZA GEOMETRIA MATEMATICA SOFTWARE EDUCATIVO