Using the Superintendent of Documents Classification System

The Superintendent of Documents (SuDocs) classification system is designed to group together publications by the same government author. Within an agency or department, publications are grouped according to the subordinate organization. The purpose of this system is to uniquely identify, logically relate, and physically arrange each publication so that all publications of a single agency or department may be found together.
  -- from FDLP Desktop

Here is how to read SuDocs call number:

Numbers following (.) are integers, not decimals.
A 1.9: precedes A 1.88:
Just as 9 comes before 88 when counting.

Which would come first?
A 57.2: or A 57.14:

Detailed explanation of the SuDoc classification system