This third volume of the Comparative Systems Laboratory (CSL) Final Technical Report is a collection of relatively independent studies performed on CSL materials. Covered in this document are studies on: (1) properties of files, including a study of the growth rate of a dictionary of index terms as influenced by number of documents in the file and a discussion of problems encountered in coding (classifying) different types of English words; (2) the nature of user questions which were searched in CSL, including a verbatim listing of the CSL questions and an index to them as well as a classification of the questions according to various criteria; (3) the relations between the system answers (documents retrieved as answers) and the questions of the user, including a textual study of documents submitted as answers and a study which attempted to optimize searching of the CSL files on the basis of known relevant and nonrelevant answers; and (4) a comparison of the CSL study with similar experiments conducted by Cyril Cleverdon in the Cranfield II project and Gerard Salton at Cornell University. A list of CSL technical reports and additional publications is appended. (Author/JB)