Ramayana
कालो द्वादश वर्षाणि शापस्यान्तो भविष्यति । मत्प्रासादाच्च राजेन्द्र व्यतीतं न स्मरिष्यसि ॥ 7-65-36 ॥
"The duration of the curse shall be twelve years, and at the end of that time it will cease; and by my grace, O lord of kings, you will not remember what has passed."
english translation