Phaladeepika
शनेश्चतुर्थी च गुरोस्तु षष्ठी दशा कुजाह्योर्यदि पऽचमी सा । कष्ट भवेद्राश्यवसानभाग- स्थितस्य दुःस्थानपतेस्तथैव ॥ २४॥
If in the order of main Dasas, the fourth happens to belong to Saturn, the sixth to Jupiter, the fifth to Mars or Rahu, eyery one of these will prove dangerous. So also will be the Dasa period of a planet occupying the end of a sign or owning a Dusstthana 6 th, 8 th or 12 th.
english translation
zanezcaturthI ca gurostu SaSThI dazA kujAhyoryadi pa'camI sA । kaSTa bhavedrAzyavasAnabhAga- sthitasya duHsthAnapatestathaiva ॥ 24॥
hk transliteration by Sanscript