Incoming Resources
- Sythoff, Leyden, 1958
- Sythoff, Leyden, 1959
- Sythoff, Leyde, 1960
- Sythoff, Leyden, 1961
- Sythoff, Leyden, 1962
- Sythoff, Leyden, 1963
- Sythoff, Leyde, 1959
- Sythoff, Leyden, 1960
- Sythoff, Leyde, 1963
- Sythoff, Leyde, 1964
- Sythoff, Leyde, 1962
- Sythoff, Leyde, 1961
- Sythoff, Leyden, 1964