group {<ncs-restraints-group-statement>} end

<ncs-restraints-group-statement> :==

  equivalence=<atom-selection>
  --{Define the ncs equivalent atoms within this group.}
  weight-ncs=<real>
  --{Force constant for ncs restraints in Kcal/mol-A**2.}
  sigb-ncs=<real>
  --{Target deviation of ncs related B-values from their average
     value in A**2.}