Published works of this oboist included concertos and studies for the oboe, english horn and flute. His playing was exceptional to the extent that Michael Haydn composed an english horn quartet for him and Mozart composed a concerto. In correspondence with his son, Leopold Mozart wrote high praises concerning Ferlendis. His performance and technique were lauded from Salzburg to London. It is thought that Ferlendis was instrumental in developing the curved tube attaching the reed to the body of the english horn. ~ Keith Johnson, All Music Guide