Prang Company. (1914). The graphic drawing books: A series of graded drawing books, presenting graphically, by means of progressive steps, a course in color, drawing, design, construction and picture study. The Prang company.
Lua i Stíl Chicago (17ú heag.)Prang Company. The Graphic Drawing Books: A Series of Graded Drawing Books, Presenting Graphically, by Means of Progressive Steps, a Course in Color, Drawing, Design, Construction and Picture Study. [New York] : Chicago, etc.]: The Prang company, 1914.
Lua MLA (8ú heag.)Prang Company. The Graphic Drawing Books: A Series of Graded Drawing Books, Presenting Graphically, by Means of Progressive Steps, a Course in Color, Drawing, Design, Construction and Picture Study. The Prang company, 1914.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.