| Canon source | Backstage source | Novel source | DITL speculation |
| # | Series | Season | Source | Comment |
| 1 | SNW | 2 | Tomorrow and Tomorrow and Tomorrow | |
| 2 | TOS | 1 | Space Seed | |
| 3 | Star Trek II : The Wrath of Khan |
| Series : | SNW Season 2 |
| Episode : | Tomorrow and Tomorrow and Tomorrow |
| Series : | TOS Season 1 |
| Episode : | Space Seed |
| Film: | Star Trek II : The Wrath of Khan |
| © Graham & Ian Kennedy | Page views : 38,727 | Last updated : 1 Mar 2004 |
