Oswald’s use of aliases is also well established. In chapter IV, the evidence relating to his repeated use of the name “A. J. Hidell,” and close variants thereof, is set forth.[C6-609] Because Oswald’s use of this pseudonym became known quickly after the assassination, investigations were conducted with regard to persons using the name Hidell or names similar to it. Subversive files, public carrier records, telegraph company records, banking and other commercial records, and other matters investigated and persons interviewed have been examined with regard to Oswald’s true name and his known alias.[C6-610] No evidence has been produced that Oswald ever used the name Hidell as a means of making undercover contact with any person. Indeed, though Oswald did prepare a counterfeit selective service card and other identification using this name, he commonly used “Hidell” to represent persons other than himself, such as the president of his nonexistent Fair Play for Cuba Committee chapter, the doctor whose name appeared on his counterfeit international certificate of vaccination, and as references on his job applications.[C6-611] Alwyn Cole, questioned document expert for the Treasury Department, testified that the false identification found on Oswald upon his arrest could have been produced by employing elementary techniques used in a photographic printing plant.[C6-612] (See app. X, pp. 571-578.) Though to perform the necessary procedures would have been difficult without the use of expensive photographic equipment, such equipment and the needed film and photographic paper were available to Oswald when he was employed from October 1962 through early April 1963 at Jaggars-Chiles-Stovall, a commercial advertising photography firm in Dallas.[C6-613] While so employed, Oswald is known to have become familiar with the mechanics of photographic enlargements, contraction, and image distortion that would have been necessary to produce his false identification, and to have used the facilities of his employer for some personal work.[C6-614] Cole testified that the cards in Oswald’s wallet did not exhibit a great deal of skill, pointing out various errors that had been committed.[C6-615] Oswald’s supervisor at Jaggars-Chiles-Stovall has stated that Oswald seemed unable to perform photographic work with precision, which was one of the main reasons for which he was ultimately discharged.[C6-616] The retouched negatives used to make Oswald’s counterfeit certificate of service identification were found among Oswald’s personal effects after his arrest, as was a rubber stamping kit apparently employed to produce his spurious international certificate of vaccination.[C6-617] There is strong evidence, therefore, that Oswald himself made the various pieces of counterfeit identification which he carried, and there is no reason to believe that he received assistance from any person in establishing his alias.