G. K. ยท Geoffrey K.
| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Long Term Almanac 2000-2050: For the Sun and Selected Stars With Concise Sight Reduction Tables, 2nd Edition | 978-0-914025-37-5 (0-914025-37-6) | 2012 |
| Long Term Almanac 2000-2050: For the Sun and Selected Stars with Concise Sight Reduction Tables, 2nd Edition | 978-0-914025-10-8 (0-914025-10-4) | 2008 |