Our system is based on collecting lists of admired science fiction books. Currently, we’re using 65 lists. If you know of other significant lists, especially from past decades, please let me know (jameswallaceharris at outlook dot com).
We also wish to express our admiration and thanks to all the other list makers and database builders who love to remember written science fiction.
In the future I plan to create a bibliography of science fiction reference works and histories.