I located this on the link shown. So the memos didn't come from an IBM Selectric.
IBM Selectric"> eliminated the jams that affected earlier designs of electric typewriter. The typeball design had many advantages, especially in eliminating of "jams" when more than one key was struck at once, and in the ability to change the typeball, allowing multiple fonts to be used in a single document. Selectric mechanisms were widely incorporated into computer terminals in the 1970s, because the typing mechanism was fast and jam-free; could be initiated by a short, low-force mechanical action; and did not require the movement of a heavy "type basket" in order to shift between lower- and upper-case.
Later models of Selectrics replaced inked fabric ribbons with "carbon film" ribbons that had a dry black or colored powder on a "once-thru" clear plastic tape. These could be used only once but they were in a cartridge that was simple to replace. They also introduced auto-correction, where a sticky tape in front of the print ribbon could remove the black-powdered image of a typed character, and introduced selectable "pitch" so that the typewriter could be switched among pica ("10 pitch"), elite ("12 pitch"), and sometimes agate ("15 pitch"), even in one document. Even so, all Selectrics were monospaced -- each and every character was the same width. Although IBM had produced a successful typebar-based machine, the IBM Executive, with proportional spacing, no proportionally-spaced Selectric office typewriter was ever introduced. There was, however, a much more expensive proportionally-spaced machine called the Selectric Composer which was considered a typesetting machine rather than a typewriter.
http://www.nationmaster.com/encyclopedia/typewriter
Well, maybe Killian was a professional typesetter using his professional typesetting machine at work.
That's what they'll say, no?
Your Nationmaster link is incorrect.
Go to the IBM website for accurate info.
http://www.ibm.com/Search?v=11&lang=en&cc=us&q=selectric&Search.x=0&Search.y=0