inductance is varied by freqency

I make a circuit as below link.
File:NPN Colpitts oscillator collector coil.svg - Wikipedia, the free encyclopedia
The ideal output is 50MHZ sinusoid wave as mentioned.

The inductor is 150nh, but in which freqency?
I use RLC meter to measure it, the value of inductance is varied by freqency.
So, I was confused in using this component(Inductor).
Does anyone can recomment some books to me? or any suggestion?
Appreciated.

Obviously, the nominal inductance has to be achieved for the intended operation frequency. If you can't measure the inductance at this frequency, you have to estimate it somehow. I guess, that a large variation (e.g. > 10 %) of measured inductance rather indicates a bad performing LCR meter than an actual inductance variation.

The reason that the measured inductance changes with frequency is that the inductor contains self-capacitance. At this sort of frequency you have to try out the inductor in YOUR layout. Any change in inductance or layout will result in a different frequency. The best way is to use an inductor which oscillates in your layout at a slightly higher frequency and add an adjustable capacitor to pull the frequency down - it will compensate for different stray capacities.
Frank