Circular letter.
- Publisher: International Union of Geological Sciences
- Print ISSN: 0444-2563
- Electronic ISSN:
- OCLC Number: 175681325
- Subject: Geology Periodicals.
- Subject code: QE
- Publication history: No. 1 (Sept. 15, 1960)-no. 18 (Feb. 15, 1967).
Print Holdings
| Archiving Institution | Program | Holdings Description | Retention |
|---|---|---|---|
| HathiTrust (HATHI) | HTDL | no.1-15 1964-66; no.1-18 (1961-67) | permanent |