Since getting Girl on Girl, I found a couple more books which showcase the work of female photographers.
Firecrackers: Female Photographers Now by Fiona Rogers and Max Houghton is a showcase of the Firecracker project to promote the work of women in the photography industry.
#girlgaze How Girls See The World by Amanda de Cadenet, with contributions by Lynsey Addario, Inez van Lamsweerde and Sam Taylor-Johnson is also a showcase of their project.
Is one book better than the other? For me, Firecrackers is a much more serious book while #girlgaze has a more tabloid feel to it. I think that it is a good thing that there are two different approaches to the problem of the lack of female representation in the industry. It is always good to have a choice.