/usr/share/psychtoolbox-3/PsychDocumentation/ is in psychtoolbox-3-common 3.0.11.20140816.dfsg1-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/psychtoolbox-3/PsychDocumentation/AntiAliasing.m
/usr/share/psychtoolbox-3/PsychDocumentation/BeampositionQueries.m
/usr/share/psychtoolbox-3/PsychDocumentation/ConserveVRAMSettings.m
/usr/share/psychtoolbox-3/PsychDocumentation/Contents.m
/usr/share/psychtoolbox-3/PsychDocumentation/DisplayOutputMappings.m
/usr/share/psychtoolbox-3/PsychDocumentation/DrawTextEncodingLocaleSettings.m
/usr/share/psychtoolbox-3/PsychDocumentation/DrawTextPlugin.m
/usr/share/psychtoolbox-3/PsychDocumentation/GStreamer.m
/usr/share/psychtoolbox-3/PsychDocumentation/InstallKinect.m
/usr/share/psychtoolbox-3/PsychDocumentation/KbQueue.html
/usr/share/psychtoolbox-3/PsychDocumentation/MirrorMode.m
/usr/share/psychtoolbox-3/PsychDocumentation/MultiDisplaySetups.m
/usr/share/psychtoolbox-3/PsychDocumentation/ProceduralShadingAPI.m
/usr/share/psychtoolbox-3/PsychDocumentation/ProgrammingTips.html
/usr/share/psychtoolbox-3/PsychDocumentation/PsychtoolboxKernelDriver.m
/usr/share/psychtoolbox-3/PsychDocumentation/SyncTrouble.m
/usr/share/psychtoolbox-3/PsychDocumentation/UseTheSource.m
/usr/share/psychtoolbox-3/PsychDocumentation/VideoRecording.m