| 其他書名 | A Study of Certain Factors in the Allocation of Arithmetic Problems Involving One, Two, Three, and Four Steps Or Processes in Reasoning |
| 出版 | Teachers college, Columbia university, 1931 |
| URL | http://books.google.com.hk/books?id=m6Xt3gq3I4oC&hl=&source=gbs_api |