Altena attended the Conservatorium van Amsterdam ( he studied contrabass ) and graduated in 1968 .
Maarten van Regteren Altena ( born January 22 , 1943 ) is a Dutch composer and contrabassist .
composer attended the Conservatorium van Amsterdam ( Maarten van Regteren Altena studied contrabass ) and graduated in 1968 .
Maarten van Regteren Altena ( born January 22 , 1943 ) is a Dutch composer and contrabassist .