1. The asymptotic behaviour of a function occuring in the theory of primes;de Bruin;J. Indian Math. Soc. (N.S.),1951
2. On the number of positive integers ≤x and free of prime factors >y;de Bruijn,1951
3. On the number of positive integers ≤x and free of prime factors >y;de Bruijn,1966
4. On some asymptotic formulas in the theory of “factorisatio numerorum”;Erdös;Ann. of Math.,1941
5. corrections to two of my papers;Erdös;Ann. of Math.,1943