Looking for TEXT on Gravitational waves

Hello,

I want to understand the derivation of gravitational waves from the linear
filed
and looking for a suitable book which also explains the purpose of all the
Gauge Transformations
including the TT gauge. Most of the books begin with Linear filed and then
couple of gauge transformations
without any explanation to arrive at the field equations then the
transformation to TT gauge etc.
My problem is that I want to know why and how this is done. I already have
Misner&Wheeler, inverno, Rindler Schutz and Hartle but none of these is
satisfying. Inverno derive very clearly but don't explain the reason of the
transformations. My request to all of you is please point me to a text which
do handle the G-waves thoroughly.
Many thanks.


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