Following members of javafx.util.Duration need to be documented:

constructor javafx.util.Duration(double)
method javafx.util.Duration.isIndefinite()
method javafx.util.Duration.isUnknown()
method javafx.util.Duration.toString()
field javafx.util.Duration.INDEFINITE
field javafx.util.Duration.ONE
field javafx.util.Duration.UNKNOWN
field javafx.util.Duration.ZERO