"Massachusetts" . . "Concord River." . . "Concord river" . "United States" . . . . "Merrimack River (N.H. and Mass.)" . . "Concord River (Mass.)" . . "Travel." . . "A week on the Concord and Merrimac rivers" . "A week on the Concord and Merrimac rivers"@en . . . . . "A week on the concord and merrimac Rivers" . . . . . . . . "A week on the concord and Merrimac Rivers" . . . . . . . . . "A week on the Concord and Merrimac [sic] rivers"@en . "A Week on the Concord and Merrimac Rivers, etc"@en . "A Week on the Concord and Merrimac rivers" . "A week on the Concord and Merrimac Rivers" . "A week on the Concord and Merrimac Rivers"@en . . . . "A week on the Concord and merrimac rivers" . . . . . . . . . . . . . . . . "A week on the concord and merrimac rivers" . . . . . . . . . . . . "A week on the Concord and Merrimac rivers; by Henry D. Thoreau"@en . . . "Merrimac River." . . "Merrimac river" . "Merrimack River (U.S.)" . .