class cartridge cdrom disk tape moreinfo none refentry rep norepeat repeat choice opt plain req language modespec BMP CGM-BINARY CGM-CHAR CGM-CLEAR DITROFF DVI EPS EQN FAX GIF GIF87a GIF89a IGES JPEG JPG linespecific PCX PIC PNG PS SGML SVG TBL TEX TIFF WMF WPG mousebutton none refentry