- Author: Marcotty Michael Ledgard Henry
- Language: Polish
- Year: 1991
Frekvenciamoduláció
djvu
- Author: Hajós Zoltán, Nagy Árpád
- Language: Hungarian
- Year: 1982
- Author: King K. N.
- Language: English
- Year: 1988
- Author: Jim Welsh John Elder
- Language: English
- Year: 1987