TY  - BOOK
AU  - Keelhoff,F.
TI  - La suspension à ressort
PY  - 1909///
CY  - Genève
PB  - Administration du Journal Suisse d'Horlogerie
KW  - Pendulum
KW  - Clocks and watches
KW  - Design and construction
KW  - advanced theory pendulum spring suspension
ER  -