| Business | Phone |
| Mca Systems Inc Po Box 339, Phoenix 21131 | (410) 666-9700 |
| Microworks Software Co Po Box 227, Phoenix 21131 | (410) 683-0345 |
| Solutron 14405 Manor Rd, Phoenix 21131 | (410) 592-3524 |
| Data Base Connection Inc 13925 Sunnybrook Rd # 550, Phoenix 21131 | (410) 628-4381 |