I don't know if interviews with composers of film music counts toward research, but Bernard Hermann gave an interview on his film score for the film version of Ray Bradbury's Fahrenheit 451 as a Bonus Feature of the DVD. The segment relates how Hermann was chosen over more electronic music using futuristic composers and why.
In Google Scholar, use "film score analysis."
Some "hits"... Gruessen aus Tucson!
Gloria
Bernard Herrmann's Vertigo: a film score handbook
D Cooper - 2001 - Greenwood Publishing Group
Max Steiner's Now, voyager: a film score guide
K Daubney - 2000 - Greenwood Publishing Group
[BOOK] Settling the score: music and the classical Hollywood film
K Kalinak - 1992 - books.google.com
... Two chapters from this book have appeared elsewhere in slightly dif- ferent form: "Max Steiner and the Classical Hollywood Film Score: An Analysis of The Informer" in Film Music I, edited by Clifford McCarty (New York: Garland, 1989), 123-42; and "The Text of Music: A Study of ...
Max Steiner and the Classical Hollywood Film Score: An Analysis of The Informer.”
K Kalinak - Film Music, 1989
[PDF] "Music as a source of emotion in film"
AJ Cohen - Music and emotion: Theory and …, 2001 - rhythmcoglab.coursepress.yale.edu
... To escape the paradox, the analysis of the acoustical information must be regarded as a preattentive step that leads the listener to inferences consistent within the ... The successful MUSIC AS A SOURCE or EMOTION IN FILM 255 director and film-score composer provide ..
thanks, Gloria. What I am looking for is not an analysis of film music, but of screenwriting for musical, especially for their musical numbers. How are they written (not composed), and does the way they are written differ from the rest of the screenplay in terms of author, form and so on.
I am also curious. This level of research is challenging because the keywords are not coming to me. I did contact the Writers' Guild West (LA HQ) with the question. Maybe somebody will take time to answer or point to a source for you.
I could get many manuscripts by hitting SEARCH at their web site. The best might be to pick screen writers of interest and gain some photo copies of their scripts. You can simply look at these yourself to see how these writers integrated songs, perhaps seeing changes or marginalia. Any academic would only be judging what you can judge firsthand. Create your own theory...