Germany: Portraits Definitives 1961-1964

I mounted all of the German Portraits definitives last night on their proper Steiner page. I think stamps of this set are some of the most common German stamps to find in older kiloware lots but, to find all of them without resorting to buying individual stamps on eBay or some other online stamp sales site is a challenge. The hardest one to find is surprisingly not either of the two highest value stamps, the 1DM or the 2DM, it is the 90pf stamp depicting Franz Oppenheimer, Sc. no. 837. The other stamp that is hard to find from this set is Sc. no. 835a, the deep green variety of Sc. no. 835 depicting Beethoven.