Charak Samhita
गतिर्द्व्येकान्तराऽन्येद्युर्दोषस्योक्ताऽन्यथा परैः। अन्येद्युष्कं ज्वरं कुर्यादपि संश्रित्य शोणितम् ॥६५॥
Some scholars opine that the different types of jwara viz the anyedushaka, tritiyaka and chaturthaka jwara manifest because of the affliction of the some alternate dhatu by the dosha.
english translation
gatirdvyekAntarA'nyedyurdoSasyoktA'nyathA paraiH। anyedyuSkaM jvaraM kuryAdapi saMzritya zoNitam ॥65॥
hk transliteration by Sanscript