North German church music in the age of Buxtehude - Webber, Geoffrey (Oxford Clarendon Press New York Oxford University Press, 1996)
Koopman's keyword-list shows interesting feature of hierarchy through single- and double underlinging, circling etc
Includes bibliographical references (p. [225]-231) and index.
Keywords: Buxtehude, Dietrich -- 1637-1707; 17th Century (1601-1700); Church music; Music history; Germany