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citations	visibility	version 1	version 1	(static HELM directory)	helena

Informal description: ""

{λ[a:Prop] .​ λ[b:Prop] .​ λ[i:{(b) .​ (a)} .​ iff ] .​ λ[a1:a]} .​ <b> .​ (a1) .​ {(i) .​ (b) .​ (a)} .​ iffe1

Validation parameters: sort hierarchy = "Z2", kernel options = ""