Adopted numbering scheme 1 - 1379 Heckmann et al. 1501 - 1799 Prosser's AP numbers (No + 1500) 2010 - 2203 Prosser's APXaaA numbers (No < 100 + 2000) 3010 - 3993 Prosser's APX1aaA numbers (No < 200 + 3000) 4010 - 4994 Prosser's APX2aaA numbers (No < 300 + 4000) The numbers 2001 to 2999 code the stars APX with number less than 100. The last digit (units) represents the letter (A - I = 1 - 9). Example: APX82B becomes 2822 The numbers 3001 to 3994 code the stars APX with number between 100 and 199. The last digit (units) represents the letter (A - I = 1 - 9). Example: APX153D becomes 3534 The numbers 4001 to 4036 code the stars APX with number between 200 and 203. The last digit (units) represents the letter (A - I = 1 - 9). Example: APX202C becomes 4023