共 50 条
- [31] TELEPHONY C, 1972 - QUESTIONS AND ANSWERS 1-3 POST OFFICE ELECTRICAL ENGINEERS JOURNAL, 1973, 66 (OCT): : S71 - S72
- [32] SYMPOSIUM UEBER SCHACHTABTEUFEN UND INJEKTIONSTECHNIK (SYMPOSIUM ON SHAFT SINKING AND INJECTION TECHNIQUES), OCTOBER 1972. Neue Bergbautechnik, 1973, 3 (04): : 249 - 326