Yopp, William Isaac
Nationality: Undetermined, possibly 
(United States)
Identities and Authority Control
- pdbooks.info ID: 10105
William Isaac Yopp Contributed to the Following:
| Title | Edition | Year of Publication | Role | Country of Publication | Possible Copyright Status | Available Online? | |||
|---|---|---|---|---|---|---|---|---|---|
|  |  | 
| ||||||
| Yopp's cipher code | 8th ed. | 1921 | Author | |  | |  | | |
| Yopp's code | 1927 | Author | | | | | | ||