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## Theorem 1 (Guo And Janicki [2]). Let

M = (X,earlier thanM ,not later thanM ,nonsimultaneousM )
be a gso-structure, i.e., M *satisfies all axioms from* (2.9) to (2.14). Let Ω be the set of all stratified orders ✁ *on X satisfying the following stratified order extension conditions:*
1. nonsimultaneousM ⊆ ✁⇆ and 2. not later thanM ⊆ ✁⌢.

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