R. S. Campbell: Memorandum. A Brief Outline of the Hai Ho Conservancy (Tientsin: [n.p.], 1931)
- Digitized: Queen’s University Belfast
- No copy listed in Wiener China-Bibliographie
R. S. Campbell: Memorandum. A Brief Outline of the Hai Ho Conservancy (Tientsin: [n.p.], 1931)