| Article ID: | iaor1992246 |
| Country: | Netherlands |
| Volume: | 10 |
| Issue: | 4 |
| Start Page Number: | 241 |
| End Page Number: | 243 |
| Publication Date: | Jun 1991 |
| Journal: | Operations Research Letters |
| Authors: | Hwang F.K., Yao Y.C. |
Kaplansky gave a formula which determines the number of ways of selecting