@TedShifrin The ISO paper sizes are specified in the standard in a table that states their width and height in millimeters. Following the principles described above, the dimensions could be calculated with the following formulas:
Format Width [m] Height [m]
An 2−1/4−n/2 21/4−n/2
Bn 2−n/2 21/2−n/2
Cn 2−1/8−n/2 23/8−n/2