The 2 oscillator circuits under are well suited for making use of crystal oscillators in collection or parallel method: Substantial-repetition-level and large-electric power picosecond regenerative amplifier according to an individual bulk Nd:GdVO4 crystal A timing reference incorporating one-crystal-silicon micromechanical resonator with a quality element of much larger than a million https://www.hxcrystals.com/seokeywords/bulk-crystal-oscillator.html