home	news	documentation	specification		implementation
foreword	milestones	version 2	version 2	(background - core - applications)	library	(static LDDL directory)
citations	visibility	version 1	version 1	(static HELM directory)	helena

Informal description: ""

{λ[a:Prop] .​ λ[b:Prop] .​ λ[c:Prop] .​ λ[d:Prop] .​ λ[o:{(c) .​ (b) .​ (a)} .​ or3 ] .​ λ[i:{(d) .​ (a)} .​ imp ] .​ λ[j:{(d) .​ (b)} .​ imp ] .​ λ[k:{(d) .​ (c)} .​ imp ]} .​ <d> .​ {(λ[x:{(c) .​ (b)} .​ or ] .​ {(k) .​ (j) .​ (x) .​ (d) .​ (c) .​ (b)} .​ orapp ) .​ (i) .​ (o) .​ (d) .​ ({(c) .​ (b)} .​ or ) .​ (a)} .​ orapp

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