Found the following hamletworks.org entries referring to line 18
View Commentary Note for 18
18
Enter Horatio, and Marcellus.
1.1.13
View Immaterial Textual Note for 18
18
Enter Horatio, and Marcellus.
1.1.13
View Material Textual Note for 18
18
Enter Horatio, and Marcellus.
1.1.13