sentences:  Stoltenberg has also had a number of solo exhibitions.Stoltenberg has received many awards for his work, including the Grand Prize from the Boston Art Festival; the First Purchase Prize of the Portland (Maine) Museum; the Worcester Art Museum Printmaking Prize; the Boston Printmakers Award; the New England Watercolor Society First Prize; the American Watercolor Society Lena Newcastle and Mario Cooper Awards; and the Boston National Historical Park Purchase Award.His works are included in the permanent collections of Boston's Museum of Fine Arts, the Boston Public Library, the Addison Gallery of American Art, the Portland (Maine) Museum of Art, the DeCordova Museum, the Art Complex at Duxbury, the Episcopal Theological School of Harvard University, the MIT Sloan School of Management, and a number of corporations and private collections.