The input symbols in the following table are to be displayed as the mathematical symbols shown below them.
| * | -> | forall | exists | /\ | \/ | => | <=> | not | in | . | |-> | lambda |
| × | -> | forall | exists | /\ | \/ | => | <=> | ¬ | e | · | |-> | \ |
When a mathematical symbol is not available (e.g., when browsing HTML on WWW) the input syntax for it may be displayed instead. Moreover, characters whose display format is in ISO Latin-1 may always be used for input. This allows the direct input of the symbols displayed as `¬ ', `×', and ` · ', and ensures that the text of a specification as shown by a WWW browser is valid input syntax (at least in the absence of display annotations).