GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
\letter A
`AlmostCrystallographicDim3', 7
`AlmostCrystallographicDim4', 7
`AlmostCrystallographicGroup', 7
`AlmostCrystallographicInfo', 9
`AlmostCrystallographicPcpDim3', 8
`AlmostCrystallographicPcpDim4', 8
`AlmostCrystallographicPcpGroup', 8
\letter B
`BettiNumber', 5
Betti numbers, \indexit{5}
`BettiNumbers', 5
\letter D
Determination of certain extensions, \indexit{6}
\letter E
Example computations I, \indexit{12}
Example computations II, \indexit{13}
Example computations III, \indexit{13}
\letter H
`HasExtensionOfType', 6
`HolonomyGroup', 8
\letter I
`IsAlmostBieberbachGroup', 5
`IsAlmostCrystallographic', 5
`IsomorphismPcpGroup', 8
\letter M
More about almost crystallographic groups, \indexit{3}
More about the type and the defining parameters, \indexit{9}
\letter N
`NaturalHomomorphismOnHolonomyGroup', 8
\letter O
`OrientationModule', 5
\letter P
Polycyclically presented groups, \indexit{8}
Properties of almost crystallographic groups, \indexit{5}
\letter R
Rational matrix groups, \indexit{7}
\letter T
The electronic versus the printed library, \indexit{10}