HANSCOM AFB, Mass.--(BUSINESS WIRE)--Two credit unions, one serving publishing powerhouse Houghton Mifflin Harcourt and the other at Hanscom Air Force Base, combined July 1 after members of the $6.4 million Houghton Mifflin Harcourt Employees FCU approved a merger with the $1.1 billion Hanscom FCU. “We are delighted to welcome over 1,000 members and the credit union staff to the Hanscom FCU family,” said Paul Marotta, Chairman of the Board for Hanscom FCU. “The leadership of Houghton Mifflin Ha