| Canon source | Backstage source | Novel source | DITL speculation |
| # | Series | Season | Source | Comment |
| 1 | TOS | 2 | Amok Time | |
| 2 | SNW | 3 | Four-and-a-Half Vulcans |
| Series : | TOS Season 2 |
| Episode : | Amok Time |
| Series : | SNW Season 3 |
| Episode : | Four-and-a-Half Vulcans |
| © Graham & Ian Kennedy | Page views : 14,099 | Last updated : 13 Apr 2014 |
