Ramayana
स हि ग्रीष्मो ऽपयाते तु वर्षारात्र उपागते । हन्यास्त्वं लवणं सौम्य सहि कालो ऽस्य दुर्मतेः ॥ 7-64-10 ॥
Therefore, when summer has passed and the rainy season has come, you should slay Lavana, O gentle one; for that is the proper time for that evil-minded one.
english translation