the Compatability matrix
then select "Change" next to storage solutions.
you can then browse down to SMO and select it:
then you should be able to check compatability with the various versions etc,
Have you tied to register on the http://support.netapp.com site?
The matrix is menu driven so you have to put in all your versions (Oracle, Windows, Snapdrive, DataOntap, SMO, etc) and it outputs any supported configurations so wont be easy to pull a PDF for you
For NSeries SMO, you should use the IBM Compatibility matrix: it is freely available here: http://www-01.ibm.com/support/docview.wss?uid=ssg1S7003903
Anyway, even on the NetApp matrix, I can't see Oracle 18.104.22.168 supported for any version of SMO: