How can I write in Latex symbols for standard or Łukasiewicz conjunction like these?

Thank you
How can I write in Latex symbols for standard or Łukasiewicz conjunction like these?

Thank you
If you don't need them in subscripts or superscripts, here's a way:
\documentclass{article}
\newcommand{\landl}{\mathbin{\landx{L}}}
\newcommand{\lands}{\mathbin{\landx{S}}}
\newcommand{\landx}[1]{%
\ooalign{%
$\land$\cr
\noalign{\kern.5ex}
\hidewidth$\scriptscriptstyle#1\mkern1.5mu$\hidewidth\cr
}%
}
\begin{document}
$a\landl b\lands c$
\end{document}

This keeps the "S" and "L" in non-italic upshape, as given in your example.
\documentclass{article}
\usepackage{stackengine}
\begin{document}
$ a \mathrel{\stackunder[-1pt]{$\wedge$}{\tiny L}}
b \mathrel{\stackunder[-1pt]{$\wedge$}{\tiny S}} c$
\end{document}

\mathop{\tt and}\nolimitsin plain TeX... – Alex Nelson Dec 30 '13 at 15:45\wedge? – ppr Dec 30 '13 at 16:02$\widehat{p}$. – ppr Dec 30 '13 at 16:13\underset(fromamsart) as the "S" is clearly not snugged up into the wedge. but it's probably somewhat a matter of taste, so the answer by @StevenSegletes seems to satisfy that condition. (but it isn't a new symbol to be considered by unicode, which is why i asked for a reference.) – barbara beeton Dec 30 '13 at 16:36