- ISSN 0010-0765 printed
- ISSN 1212-6950 electronic
1955, Volume 20
- Issue 6 contents (June, pp. 1261-1509)
- Issue 5 contents (May, pp. 1009-1255)
- Issue 4 contents (April, pp. 757-1008)
- Issue 3 contents (March, pp. 521-726)
- Issue 2 contents (February, pp. 265-511)
- Issue 1 contents (January, pp. 1-260)
