Gate drive transformers - Recommended literature?

Hi,
Does anyone have any good literature regarding isolation gate drive transformers (pulse transformers) and their respective drive circuits?
I know there are different topologies out there that are used that depend on the application requirements at hand. But I do find it somewhat challenging to find well written app notes and/or lectures notes on the topic. My particular applications can be described as high voltages, low currents, with 120kHz carrier.

Thanks.