Valmiki Ramayana Bala Kanda Sarga 4 Shloka 15

 सर्वे all, मुनय: sages, तत् श्रुत्वा having heard that, परम् great, विस्मयम् wonder, आगता: having experienced, बाष्पपर्याकुलेक्षणा: been overcome with tears of joy in their eyes, साधु साधु इति excellent, excellent, तौ about Kusa and Lava, ऊचु: exclaimed.

 All the sages having heard the chanting (of that glorious kavya), experienced great astonishment. Overcome with tears of joy in their eyes, they praised them, exclaiming "Excellent, Excellent".