Use the printed form for the part numbers

Error²Federal courts, Illinois courts21st and 22nd editions

A multipart article names its parts in parentheses after the main title: one part takes “pt.”, several take “pts.”, and an ampersand joins two numbers.¹

1. 1R. 16.7.5 Multipart Articles.
2. 2An error: the rule in note 1 allows one form, and this is not it.