| Dialog(R) file 226: Trademarkscan (R) US FED, Vision Inspired Partnership Compuserve Network Services, 1941210, first use Apr. 30, 1994, Dec. 12, 1995. |
| Dialog (R) File 226: Trademark scan (R) US Fed, CompuServe CD, pending, first use Mar. 31, 1994. |
| The Icon Book, William Horton, John Wiley & Sons, Inc., goal and hard disk icons, p. 383, 1994. |
| The Macintosh Bible, Second Edition, Goldstein and Blair, oval and filled oval images, p. 173, 1988. |
| Trademark & Symbols, vol. 2: Symbolical Designs, #482, p. 93, 1973. |
| Symbol Sourcebook, Henry Dreyfuss, Van Nostrand Reinhold, elliptical images, pp.175-176, 1972. |