So I came across this collpitt's oscillator in a research paper that I am thinking of implementing but it looks quite different from other configurations and I would really appreciate some help understanding it. These are my questions specifically:

1. Where is the tank circuit? Which capacitors are participating?
2. Where is the capacitor divider and where is the feedback to the transistor?

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I came across this in a research paper which claimed that inductively coupling another tank circuit with the oscillator increases the emitter current with maximum current at resonant frequency. Can someone also help me understand the reason for this?