Text ( visual ) : unmediated A field guide to eastern butterflies / Paul A. Opler ; illustrated by Vichai Malikul. -- : pbk. -- Boston : Houghton Mifflin , c1992. -- xvii, 396 p. : ill.(some col.), maps ; 19 cm. -- (The Peterson field guide series ; 4). -- "Sponsored by the National Audubon Society, the National Wildlife Federation, and the Roger Tory Peterson Institute." ; Includes 48 leaves of col. plates ; Includes bibliographical references (p. 359-362) and indexes. -- ISBN 039563279X ; (BB1211801X) ; https://ci.nii.ac.jp/ncid/BB1211801X Other Title(s): Eastern butterflies. -- Author Heading(s): Opler, Paul A. ; Malikul, Vichai ; National Audubon Society ; National Wildlife Federation ; Roger Tory Peterson Institute. -- Classification(s): LCC : QL551.E16 ; DC20 : 595.78/9/097 ; NDC9 : 486.8. -- Subject Heading(s): LCSH : Butterflies -- East (U.S.) ; LCSH : Butterflies -- Canada, Eastern ; LCSH : Butterflies -- Greenland