Found the following hamletworks.org entries referring to line 20

View Commentary Note for 11
11 Bar. Tis now strooke twelfe, get thee to bed Francisco,1.1.7

View Commentary Note for 1
The Tragedie of 0{B1r} <nn4v>
H A M L E T
Prince of Denmarke.
1 <Actus Primus. Scœna Prima.> 1.1 

View Commentary Note for 20
20 Hora. Friends to this ground.1.1.15

View Material Textual Note for 20
20 Hora. Friends to this ground.1.1.15

View Commentary Note for 5-6
5-6 Fran. Nay answere me. Stand and vnfolde | your selfe.1.1.2

View Commentary Note for 7
7 Bar. Long liue the King,1.1.3