# How to make theorem title (such as Theorem, lemma, definition, etc) in margin while theorem number as usual.

How to make the theorem style like:

1.1.3. There is a theorem.         Theorem

it may be several lines.

The theorem 1.1.3 end.

1.1.1. There is a lemma.           lemma

The lemma 1.1.1 end.

(for oneside documentclass)

Use ntheorem:

\documentclass{article}
\usepackage{ntheorem}
\makeatletter
\newtheoremstyle{marginname}%