TY - BOOK T1 - Inventions T2 - Then & now A2 - Ashworth, F. J. LA - English PP - Edinburgh PB - McDougall YR - 1978 UL - https://glotrec.wdi-testing.gei.de/cat/Record/gei564536989 SN - 0715713140 KW - Schulbuch ER -