William Leyerle, Leyerle Publications, studio, soloist, recital, voice class, pedagogy class, foreign language, dictation class, choral director, choral singer, opera director, opera conductor, voice teacher, voice coach, vocal specialist, phonetic translation, nico castel, beaumont glass, schubert, robert gartside, maurice ravel, gabriel faure, andrew foldi, phillip smith, gordon myers, opera libretti, song anthologies, art song texts, song groups, technical music, martha gerhart, mozart, puccini, verdi, richard faith, hugo wolf, blue willow designs