Houghton Mifflin Co.

The company was formerly known as Houghton Mifflin Company but changed its name following the 2007 acquisition of Harcourt Publishing.  Houghton Mifflin Harcourt is an educational and trade publisher in the United States. Headquartered in Boston's Back Bay, it publishes textbooks, instructional technology materials, assessments, reference works, and fiction and non-fiction for both young readers and adults.

-Wikipedia