I was trying to derive a model for Opamp Hartley oscillator. I used a R at mouth of opam to increase the output impedance. So i tried including it in calculation. As the opamp is modeled as output voltage of Avi so using a R in series with it with help me to reconfigure the circuit changing the circuit voltage source into a current source using source transformation theorem. Here are my calculations. Can you tell me where i messed up.