To read a call number, consider each section independently. 
- BF
Read the 1st line in alphabetical order: A, B, BF, C, D, DC...
- 1556
Read the 2nd line as a whole number: 1, 2, 3, 32, 100, 101, 1000, 1100, 1556, 2000, 3000...
- Z66
First read the 3rd line alphabetically. Then read the following number as a decimal: C51, D49, Z616, Z66, Z8
- 2010
The last line is the year, and is read in chronological order: 1989, 1992, 2000, 2010, 2016
