BibTeX: gordon87 fixed
extra space removed
'passed in' vs 'passed on' in the preceding paragraph (more fixes needed)
consistent use of semicolons in enumeration
extra space after displayed Z removed
typo: 'ertain' instead of 'certain'
punctuation within {itemize} added
extra inter-sentence space after 'E.g.' removed
extra space removed (similar to 65adb22)
typos: double 'the the'
typos: double 'as as'
typos: double 'is is'
typos: double 'of of'
typos: double 'that that'
typos: double 'for for'
typos: double 'in in'
typos: double 'from from'
typos: double 'and and'
typos: double 'at at'