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

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