\begin{thebibliography}{}

\bibitem[Haible, 1988]{cloccseq}
Haible, B. (1988).
\newblock {The Abstract Datatype {\it Sequence}}.
\newblock Technical report, University of Karlsruhe.
\newblock \url{http://tinyurl.com/yy3eys}.

\bibitem[Haible, 2006]{clispseq}
Haible, B. (2006).
\newblock personal communication.

\bibitem[Pitman and Chapman, 1994]{CLtS}
Pitman, K. and Chapman, K., editors (1994).
\newblock {\em Information Technology -- Programming Language -- Common Lisp}.
\newblock Number 226--1994 in INCITS. ANSI.

\bibitem[Pitman, 1991]{ConcatenateSequence}
Pitman, K.~M. (1991).
\newblock {Issue \texttt{CONCATENATE-SEQUENCE}}.
\newblock Technical report, ANSI.
\newblock \url{http://www.lisp.org/HyperSpec/Issues/iss073-writeup.html}.

\bibitem[Rhodes, 2007]{UserExtSequences}
Rhodes, C. (2007).
\newblock User-extensible sequences.
\newblock in preparation.

\end{thebibliography}