Charak Samhita
शान्तिरामाशयोत्थानां व्याधीनां लङ्घनक्रिया । ज्वरस्यैकस्य चाप्येका शान्तिर्लङ्घनमुच्यते ॥३१॥
The diseases originating from amashaya are cured by langhana (fasting), only whereas only a single disease entity jwara also can be treated by the single therapy of langhana (fasting).
english translation
zAntirAmAzayotthAnAM vyAdhInAM laGghanakriyA । jvarasyaikasya cApyekA zAntirlaGghanamucyate ॥31॥
hk transliteration by Sanscript