The SuDocs call number system is based on the government agency which released the document. The next part of the call number identifies the series or type of publication. The remaining parts of the call number identify the individual publication. The call numbers file alphabetically by letter and then in numerical order by the first group of numbers, then the next group, etc.
All numbers are whole numbers.
Then numerically by the number, stopping at the period. Then numerically by the whole number down to the next slash, period, or colon. If at any time after the first period you must choose between a number and a letter, letters go before numbers. Continue looking by the whole number or letter up to the next punctuation mark until the end of the call number. 857 Government documents may be published in paper format or in microfiche format.