Found the following hamletworks.org entries referring to line 694

View Commentary Note for 629
629 That I will speake to thee, Ile call thee Hamlet,1.4.44

View Commentary Note for 694
694 Ghost. I am thy fathers spirit,1.5.9

View Immaterial Textual Note for 694
694 Ghost. I am thy fathers spirit,1.5.9

View Material Textual Note for 694
694 Ghost. I am thy fathers spirit,1.5.9