Sorting by Dewey code does not seem to work correctly. Items with more digits are sorted as if they were higher. Thus, the code "512" is sorted before "005.13".
Dewey codes should be sorted numerically by the first three digits and alphabetically after that.
Bookpedia: Dewey sorting
Re: Bookpedia: Dewey sorting
This is a known issue when using the European format for numbers in your system preferences. Bookpedia interprets the period as a thousand separator and 005.13 becomes higher than 512. Thank you for reminding us about the issue and will look at it again see if there is a solution.