Ceiling balloon
Top View
- AVIATION WEATHER OBSERVATIONS for Supplementary Aviation Weather Reporting Stations (SAWRS) MANUAL OBSERVATIONS
- MANOBS Manual of Surface Weather Observations
- No. 4. the Content Is Divided Into Six Chapters Observation, Sky Conditions, Ceiling Heights, Sky
- Meteorological
- Glossar Meteorologie Englisch-Deutsch, Deutsch-Englisch
- Canada Canada GUIDE 92-1