Shiva Purana

siva.sh/siva-purana/kotirudra-samhita/6/49

श्वेतवर्णा तदा सा गौर्द्रुतं श्यामा व्यदृश्यत ।। अहो च दृश्यतां लोकाश्चुक्रुशुश्च परस्परम् ।। ४९।।

sanskrit

The cow which had been white in colour turned black immediately. People cried to one another “O see O see.”

english translation

zvetavarNA tadA sA gaurdrutaM zyAmA vyadRzyata || aho ca dRzyatAM lokAzcukruzuzca parasparam || 49||

hk transliteration by Sanscript