@unnumberedsec, @appendixsec, @headingThe @unnumberedsec, @appendixsec, and @heading
commands are, respectively, the unnumbered, appendix-like, and
heading-like equivalents of the @section command. 
(See @section.)
     
@unnumberedsec
     @unnumberedsec command may be used within an
unnumbered chapter or within a regular chapter or appendix to
provide an unnumbered section.
     @appendixsec
     @appendixsection
     @appendixsection is a longer spelling of the
@appendixsec command; the two are synonymous.
     Conventionally, the @appendixsec or @appendixsection
command is used only within appendices.
     
@heading
     @heading command anywhere you wish for a
section-style heading that will not appear in the table of contents.