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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:{(b) .​ (a)} .​ or ] .​ λ[i:{(c) .​ (a)} .​ imp ] .​ λ[j:{(d) .​ (b)} .​ imp ]} .​ <{(d) .​ (c)} .​ or > .​ {(i) .​ ({(j) .​ (o) .​ (d) .​ (b) .​ (a)} .​ th8 ) .​ (c) .​ (d) .​ (a)} .​ th7

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