\begin{thebibliography}{6}
\providecommand{\natexlab}[1]{#1}
\expandafter\ifx\csname urlstyle\endcsname\relax
  \providecommand{\doi}[1]{doi:\discretionary{}{}{}#1}\else
  \providecommand{\doi}{doi:\discretionary{}{}{}\begingroup
  \urlstyle{rm}\Url}\fi

\bibitem[{\textit{Courant and Hilbert}(1989)}]{Courant89_2}
Courant, R., and D.~Hilbert (1989), \textit{Methods of Mathematical Physics,
  Volume 2: Differential Equations}, 852 pp., John Wiley and Sons.

\bibitem[{\textit{Sekine and Parker}(1992)}]{Sekine92_1}
Sekine, M., and G.~Parker (1992), Bed-load transport on transverse slope. i,
  \textit{J. Hydraul. Eng.}, \textit{118}(4), 513--535,
  \doi{10.1061/(ASCE)0733-9429(1992)118:4(513)}.

\bibitem[{\textit{Sieben}(1994)}]{Sieben94}
Sieben, A. (1994), Notes on the mathematical modelling of alluvial mountain
  rivers with graded sediment, \textit{Tech. Rep. 94--3}, Delft University of
  Technology, The Netherlands.

\bibitem[{\textit{Sieben}(1997)}]{Sieben97_PhD}
Sieben, J. (1997), Modelling of hydraulics and morphology in mountain rivers,
  Ph.D. thesis, Delft University of Technology.

\bibitem[{\textit{Sloff}(1992)}]{Sloff92}
Sloff, C.~J. (1992), The method of characteristics applied to analyse 2{DH}
  models, \textit{Tech. Rep. 92--4}, Delft University of Technology, The
  Netherlands.

\bibitem[{\textit{Sloff}(1993)}]{Sloff93}
Sloff, K. (1993), Analysis of basic equations for sediment-laden flows,
  \textit{techreport 93-8}, Delft University of Technology, The Netherlands.

\end{thebibliography}