Compilation of secondary verb roots derived by adding णिच्-प्रत्यय to original roots. pp102. Compiled by Dr.Pushpa Dixit. ṇatvaṇijantam (णत्वणिजन्तम्) (GR131) is an excellent book to understand णिजन्त-forms.
As per Panini, तिङ्शित् सार्वधातुकम् (३-४-११३) and आर्धधातुकं शेषः (३-४-११४). An exceellent reference book to know verb forms in both these situations.