HarperCollins · Littlehampton Book Services Ltd
| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| The Penguins are Coming | 978-0-437-90065-4 (0-437-90065-7) | 1970 |
| The Penguins are Coming! | 978-0-06-024693-8 (0-06-024693-6) | 1969 |
L.P. · R. L · R. P. · Richard L. Penney · Russell L. Penney