A biconditional relation is a relation between a consequent and a condition. The consequent is true or in force if and only if the condition is true, with the result that there is a conditional relation in both directions between the related propositions .
(English)
If and only if he goes, I go.
Note: This sequence also has the incidental meaning of If I go, he goes.
Comrie, Bernard. 1986. "Conditionals: A typology." In Traugott 1986