XSLT 2.0 and XPath 2.0 Programmer's Reference, 4th Edition (821 page)

existential properties of

GeneralComp

not() and

quantification and

some
expression and

!=
operator

GeneralComp

not() and

usage/avoidance of

<

character

escaped as
<

GeneralComp

<=
operator

GeneralComp

>

escaped as
&glt;

GeneralComp

=
operator