His output for organ includes six organ symphonies , `` 24 Fantasy Pieces '' ( which includes his famous `` Carillon de Westminster '' ) , and `` 24 Pieces in Free Style '' , among other works .
He wrote a lot of music for the organ , including six large works called symphonies , `` 24 Fantasy Pieces '' ( which includes his famous `` Carillon de Westminster '' ) , and `` 24 Pieces In Free Style '' .