John Wallace Spencer
Books 1
| No Earthly Explanation |
Copyright Holder 3
 | Limbo of the Lost | Mass-Market Paperback |
 | No Earthly Explanation (Mankind: A Space Experiment) | Mass-Market Paperback |
| No Earthly Explanation (Mankind: A Space Experiment) | Paperback |
| No Earthly Explanation |
| Limbo of the Lost | Mass-Market Paperback |
| No Earthly Explanation (Mankind: A Space Experiment) | Mass-Market Paperback |
| No Earthly Explanation (Mankind: A Space Experiment) | Paperback |