Matthew Haislip's varied influences as a composer include such composers as Igor Stravinsky, John Adams, Bernard Herrmann, Henryk Gorecki, Claude Debussy, Leoš Janáček, Sergei Prokofiev, Ludwig van Beethoven, Henry Cowell, Francis Poulenc, Philip Glass, Reynaldo Hahn, Howard Blake, John Williams, Gustav Mahler, Giacomo Puccini, Leonard Bernstein, Olivier Messiaen, Dmitri Shostakovich, Astor Piazzolla, Jean Sibelius, and Maurice Ravel, as well as such popular music influences as Yes, Phil Keaggy, Keane, Paul McCartney, and Daft Punk.
Dr. Haislip's etude book, Ten Character Studies for Horn, has recently been published by BrownWood Publishing. 
The link to the book's publishing page is below:
Perelandra for solo horn (2017)
Cathedral Fanfare for brass quintet (2017)
Blue October for nine horns (2016)
Ex Aequo for horn and trombone (2016)
Brass Quintet No. 1 in D major (2015)
Ten Character Studies for Horn (2015)
Two Etudes for Piano (2009)