He had asked for his motet Ave regina celorum to be sung for him as he died , with pleas for mercy to be read between some of the movements , but there was not enough time for this to be arranged , so it was sung at his funeral instead . He had requested that his motet Ave regina celorum be sung for him as he died , with pleas for mercy interpolated between verses of the antiphon , but time was insufficient for this to be arranged .