--- a/doc/interpreter/plot.txi
+++ b/doc/interpreter/plot.txi
@@ -1709,7 +1709,79 @@
 @cindex series objects
 @cindex error bar series
 
-TO BE WRITTEN
+Error bar series are created by the @code{errorbar} function. Each 
+@code{hgrroup} element contains two line objects represnting the data and
+the errorbars separately. The properties of the error bar series are
+
+@table @code
+@item color
+The RGB color or color name of the line objects of the error bars. @xref{Colors}.
+
+@item linewidth
+@itemx linestyle
+The line width and style of the line objects of the error bars. @xref{Line Styles}.
+
+@item marker
+@itemx markeredgecolor
+@itemx markerfacecolor
+@itemx markersize
+The line and fill color of the markers on the error bars. @xref{Colors}.
+
+@item xdata
+@itemx ydata
+@itemx ldata
+@itemx udata
+@itemx xldata
+@itemx xudata
+The original x, y, l, u, xl, xu data of the error bars.
+
+@item xdatasource
+@itemx ydatasource
+@itemx ldatasource
+@itemx udatasource
+@itemx xldatasource
+@itemx xudatasource
+Data source variables.
+@end table
+
+@node Surface group
+@subsubsection Surface group
+@cindex group objects
+@cindex surface group
+
+Surface group objects are created by the @code{surf} or @code{mesh}
+functions, but are equally one of the handles returned by the @code{surfc}
+or @code{meshc} functions. The surface group is of the type @code{surface}.
+
+The properties of the surface group are
+
+@table @code
+@item edgecolor
+@item facecolor
+The RGB color or color name of the edges or faces of the surface. @xref{Colors}.
+
+@item linewidth
+@itemx linestyle
+The line width and style of the lines on the surface. @xref{Line Styles}.
+
+@item marker
+@itemx markeredgecolor
+@itemx markerfacecolor
+@itemx markersize
+The line and fill color of the markers on the surface. @xref{Colors}.
+
+@item xdata
+@itemx ydata
+@itemx zdata
+@item cdata
+The original x, y, z and c data.
+
+@item xdatasource
+@itemx ydatasource
+@itemx zdatasource
+@itemx cdatasource
+Data source variables.
+@end table
 
 @node Line series
 @subsubsection Line series