Modern practice of the electric telegraph a handbook for electricians and operators /
Pope, Frank Leonard 1840-1895,
Modern practice of the electric telegraph a handbook for electricians and operators / By Frank l. pope - 10 # rev. and enl. - viii, [9], 160 páginas
Telégrafo--Operadores manuales
TK5263 / P86 1877
Modern practice of the electric telegraph a handbook for electricians and operators / By Frank l. pope - 10 # rev. and enl. - viii, [9], 160 páginas
Telégrafo--Operadores manuales
TK5263 / P86 1877