US 2706249, Vackář, Jiří, "Stabilization of resonant circuits", published 10. februar 1950, issued 12. april 1955
f6evt.fr
Vackář, Jiří (december 1949), LC Oscillators and their Frequency Stability(PDF), Tesla Technial Reports, Prague, Czechoslovakia: Tesla National Corporation, UDC 621.396.615.12, arkiveret(PDF) fra originalen 19. februar 2012, hentet 6. juni 2015
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Vackář, Jiří (december 1949), LC Oscillators and their Frequency Stability(PDF), Tesla Technial Reports, Prague, Czechoslovakia: Tesla National Corporation, UDC 621.396.615.12, arkiveret(PDF) fra originalen 19. februar 2012, hentet 6. juni 2015