<chr_abbr type="frq" class="ss" expan="et" cert="yes">et2</chr_abbr> delautre a<chr_abbr type="reg" class="dc" expan="" cert="no">p-hbar</chr_abbr><chr_var letter="s" var="long">∫</chr_var> <chr_var letter="s" var="long">∫</chr_var>et<chr_abbr type="reg" class="dc" expan="" cert="no">re-hbar</chr_abbr>ca 