Someone just loaned me the CD "Characters" by Quirijin Van Regteren Altena. A nice selection of 20th century music for bass and piano, including the Hindemith sonata and lesser-known works by Andriessen, Ginastera, Desencios, Thilman, and Alec Wilder. Is he related to Maarten Altena? They look a lot alike. I couldn't find anything online.