Description: Offered is a collection of approximately ten (10) full unused US commemorative postage stamp sheets, neatly preserved inside a classic blue "Mint Sheet File" album. This selection highlights iconic 1970s and 1980s United States Postal Service commemorative issues, featuring rich historical artwork and popular thematic designs.  Featured Sheets Include: 1976 "Spirit of '76" Bicentennial Strip/Sheet: 13¢ issues depicting Archibald Willard's famous painting.  1974 Universal Postal Union Centenary: 10¢ sheets showcasing historical artwork depicting letter writing and postal history.  1982 State Birds and Flowers Issue: Complete 50-stamp sheet of 20¢ values illustrated by Arthur and Alan Singer.  Carl Sandburg Commemorative Issue: 13¢ mint sheets.  Hot Air Balloons & Winter Olympics Issues: 20¢ thematic sheets.  Includes: Blue protective "Mint Sheet File" binder folder.