1. The Superintendent of Documents (SuDoc) classification number begins with a capital letter or letters representing a government department or agency. (A - Agriculture Dept., C - Commerce Dept., ED - Education Dept., etc.) The U. S. Congress uses the letters X and Y.
  2. The numbers that follow these letters represent the office of a particular department. For instance, all Internal Revenue Service publications will be given a number beginning with T 22. The numbers after the decimal point represent second and subsequent level offices.
  3. Numbers immediately following the colon indicate numbered series, volumes or dates. Letters and numbers immediately following the colon are based on a system which organizes materials alphabetically by subject.
  4. In general, documents are shelved in alphabetical and numerical order.
      5. C 3.24/8: IN 23
      C 3.25: AF 48
      NAS 1.2: FR 76
      NS 5: 100
  5. This is not a decimal system. Numbers between punctuation are treated as individual whole numbers.
      6. D 1.2: EX 83
      D 1.16: TO 75
      D 1.23: NA 42
      D 1.23/2: CR 76
      D 1.23/2-3: AL 23
      D 1.23/2-11: LI 45
      D 1.142: LE 78
  6. Numbers precede letters.
      7. C 61.12: 89-7
      C 61.12: AM 32
  7. Senate Hearings and Prints:
    S.HRG. then S.PRT. by congress number. After that, numbers, and then alphabetically.
      8. Y 4.B 85/2: S.HRG.100-45
      Y 4.B 85/2: S.PRT.100-37
      Y 4.B 85/2: S.HRG.101-13
      Y 4.B 85/2: S.PRT.101-20
      Y 4.B 85/2: 100-9
      Y 4.B 85/2: AR 56
  8. Microfiche is filed in the same way as paper except Foreign Broadcast Information Service (PREX 7.10 & PREX 7.13), House and Senate Reports and Documents (Y 1.1), and Bills and Resolutions (Y 1.4) are filed in the microfiche cabinets at the north end of the reference area. A finding aid for Y 1.4 is kept in the black binder in the microfiche area.
  9. Serial set volumes are shelved at the end of the document collection.