1 Corinthians 15:51 King James Bible (Cambridge Ed.)
Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed,
1 Corinthians 15:6 King James 2000 Bible (©2003)
After that, he was seen of over five hundred brethren at once; of whom the greater part remain until now, but some are fallen asleep.
1 Corinthians 15:18 King James Bible (Cambridge Ed.)
Then they also which are fallen asleep in Christ are perished.
These scriptures are my references to "sleep". When referencing the "lost" in the NT many times refer to eternal death or just died, death, etc.
I appreciated this response. Thanks