Not as much research as there should be on female anatomy and sexual response (ironically); for comparison, scientists didn't discover that the clitoris has an entire subsurface band of erectile tissue until 1992. There's plenty in there to discover yet.
Still, there's plenty of legit sci evidence that a. a "female prostate" exists, and b. it produces ejaculate that is distinct from urine. Not to mention, you know, my own physical concrete experience, with my own damn body and those of others.
Psych Today article on the history of scientists and the G Spot, beginning in 1672 and Regnier de Graaf, through Grafenberg and Skene and so forth.
http://www.psychologytoday.com/blog/shameless-woman/201209/g-spot-amnesia-or-350-years-rediscovery
There's also the entire body of work of Dr. Milan Zaviacic, who has devoted his career to (successfully) finding tissue and hormonal evidence of the female prostate. His research has helped women who were being erroneously treated for urinary incontinence.
Another article on the female prostate and its ejaculate, "The Female Prostate: The Newly Recognized Organ of the Female Genitourinary System". Quote: "The existence of the human female prostate had been a controversial topic in modern urological medicine, frequently ignored, or thought it was a vestigial organ.
Today this perception is antiquated, recent investigations recognize it as a functional gland capable of performing the same functions as the male prostate gland."
http://www.scribd.com/doc/42970145/...ized-Organ-of-the-Female-Genitourinary-System
Another scientific lit review on the subject:
http://mackiller.tripod.com/femaleejaculationlp.pdf
And another article, from the Electronic Journal Of Human Sexuality. Quote: "Analyses of the specimens showed that concentrations of prostatic acid phosphatase (PAP) were significantly higher while concentrations of urea and creatinine, primary components of urine, were significantly lower in the four expulsion specimens than in three urine specimens from the same subject. The authors concluded that, '
the dissimilarity of chemical composition of the orgasmic expulsion and urine specimens indicates that the expulsion in this subject was not a manifestation of urinary incontinence.' They also hypothesized that 'the expulsion is largely a glandular secretion' and that, 'the PAP suggests that at least part of the glandular secretion came from prostatic tissue.'"
http://www.ejhs.org/volume4/Schubach/Chap2.html
Or check out RN Sheri Winston's book on the subject, _Women's Anatomy of Arousal_. Very complete and scientifically accurate, as well as amusing, take on the subject.
http://www.amazon.com/Womens-Anatomy-Arousal-Sheri-Winston/dp/057803395X
Or you could read Deborah Sundahl's 2003 book on female ejaculation, _Female Ejaculation and the G Spot_:
http://www.amazon.com/Female-Ejacul...=UTF8&qid=1418585975&sr=1-2&keywords=zaviacic
Female ejaculation is a thing for plenty of folks; there's variation between individuals, and many women, including me and several friends/lovers of mine can do it just fine. And piss play is fine if that's your thing, but ejaculation is quite distinct. You know it when you taste it.