IsRing($T$;${\it plus}$;${\it zero}$;${\it neg}$;${\it times}$;${\it one}$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$IsGroup($T$;${\it plus}$;${\it zero}$;${\it neg}$) \& IsMonoid($T$;${\it times}$;${\it one}$) \& BiLinear($T$;${\it plus}$;${\it times}$)