Complex sentence: The first printing of the 1980 "New Grove Dictionary of Music and Musicians" contains two fictitious entries: on Guglielmo Baldini, a non-existent Italian composer, and Dag Henrik Esrum-Hellerup, who purportedly composed a small amount of music for flute.
Split into simpler sentences: The first printing of the 1980 "New Grove Dictionary of Music and Musicians" contains two fictitious entries. The second was on the subject of Dag Henrik Esrum-Hellerup, who purportedly composed a small amount of music for flute.