Perhaps you should try some spelling variations:
"formal languages and automatic theorem" » "formal languages and automated theorem", "formal languages and automata theory", "formal language and automatic theorem"
"formal languages and automatic theory" » "formal languages and automation theory", "formal languages and automata theory", "formal languages and automated theory", "formal language and automatic theory"
"formal languages and axiomatic theory" » "formal language and axiomatic theory", "formal languages and aromatic theory"

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