How do I purl 2 tog dbl?

I have a baby blanket pattern that calls for purl 2 tog dbl. I don’t know if this actually means Purl 4 sts tog, or purl 2 tog twice, or something else entirely. I am at a stand-still until I can get help resolving my issue…

Could it possibly be a typo? I’ve seen P2tog tbl (through the back loop), but never dbl. I wonder if that’s what they meant? Do you have the pattern?

Duh…I [I]know[/I] you have the pattern…what I meant is, are there yarn overs on that same row or could you write out the line where that mystery stitch is?

I vote for a typo too. Is there a similar row where it says p2tog tbl instead?