CC Madhya 20.176

ye-kāle dvibhuja, nāma — vaibhava-prakāśa
caturbhuja haile, nāma — prābhava-prakāśa
Word for word: 
ye-kāle dvi-bhuja — when the Lord appears as two-handed; nāma — named; vaibhava-prakāśa — vaibhava-prakāśa; catur-bhuja haile — when He becomes four-handed; nāma — named; prābhava-prakāśa — prābhava-prakāśa.
Translation: 
“When the Lord is two-handed He is called vaibhava-prakāśa, and when He is four-handed He is called prābhava-prakāśa.