| Date | Publication | Publisher | Type | Page | |
|---|---|---|---|---|---|
| October 1956 |
|
New Worlds Science Fiction, October 1956 | Nova Publications Ltd. | MAGAZINE | 7 |
| November 1956 |
|
New Worlds Science Fiction, November 1956 | Nova Publications Ltd. | MAGAZINE | 78 |
| December 1956 |
|
New Worlds Science Fiction, December 1956 | Nova Publications Ltd. | MAGAZINE | 79 |
| 1957 |
|
Master of Life and Death / The Secret Visitors | Ace Books | Omnibus | 5 |
| May 1958 |
|
Häpna!, maj 1958 | Grafiska Förlaget Kindberg & Söner | MAGAZINE | |
| June 1958 |
|
Häpna!, juni 1958 | Grafiska Förlaget Kindberg & Söner | MAGAZINE | 71 |
| July 1958 |
|
Häpna!, juli-augusti 1958 | Grafiska Förlaget Kindberg & Söner | MAGAZINE | 71 |
| September 1958 |
|
Häpna!, september 1958 | Grafiska Förlaget Kindberg & Söner | MAGAZINE | |
| October 1958 |
|
Häpna!, oktober 1958 | Grafiska Förlaget Kindberg & Söner | MAGAZINE | 83 |
| October 1958 |
|
Die AuĂźerirdischen | Moewig | Novel | 3 |
| 1961 |
|
The Secret Visitors | Digit Books | Novel | 5 |
| 1963 |
|
The Secret Visitors | Digit Books | Novel | |
| October 1964 |
|
Futuria #2 | Zillitti Editore | MAGAZINE | 3 |
| 1967 |
|
The Secret Visitors | Ace Books | Novel | 5 |
| June 1967 |
|
Die AuĂźerirdischen | Moewig | Novel | 5 |
| February 1971 |
|
The Secret Visitors | New English Library | Novel | |
| April 1974 | The Secret Visitors | White Lion | Novel | ||
| February 1979 |
|
Die AuĂźerirdischen | Pabel | Novel |