Paul Damjakob (*1939) was Organist at Würzburg-Cathedral (GER), where he had the famous and mighty Klais-Organ, which is similar colourful as the Marcussen-Organ in Rotterdam.
Damjakob is well known for his fantastic improvisations. Some of his improvisations were written down after a recording.
This Meditation "Ave Maria zart" was reconstructed by Hubert Foersch, and the score is available:
Jubilate-Verlag Eichstätt RM1016