Found the following hamletworks.org entries referring to line 3390-1

View Commentary Note for 3390-91
3390-1 Ham. To what base vses wee may returne Horatio ? | Why may not 3390-1 

View Material Textual Note for 3390-91
3390-1 Ham. To what base vses wee may returne Horatio ? | Why may not 3390-1