INDEX KEWENSIS
Older and/or conserved family names such as CRUCIFERAE remain, but the new family name BRASSICACEAE does not appear in the index; so if you don't find the family name, try the genus name.
If you are using IKew and see a highlighted author link to APN, or vice versa, those links cannot be relied upon in every case since both databases originated as books, their writing was not a coordinated effort, and not all the links have even been made. It may therefore be more efficient to search APN directly for the author's name, but remember that IKew and APN do not necessarily use the same abbreviations.