Phaladeepika
लग्नात्सुखेश्वरांशेशदशायां च पितृक्षयः । सुखनाथदशायां वा पितृतुल्यमृतिं वदेत् ॥ ४॥
The demise of the father or of one similarly placed may occur during the Dasa of the planet owning the Navamsa occupied by the lord of the 4 th house from the Lagna. Or, the same eveat may also happen during the Dasa of the planet owning the 4 th house.
english translation
lagnAtsukhezvarAMzezadazAyAM ca pitRkSayaH । sukhanAthadazAyAM vA pitRtulyamRtiM vadet ॥ 4॥
hk transliteration by Sanscript