Perhaps you should try some spelling variations:
"mathematics and its applications, soviet theories" » "mathematics and its applications, soviet theory", "mathematics and its applications, comet theories", "mathematics and its applications, secret theories"
"mathematics and its application, soviet theories" » "mathematics and its application, soviet theory", "mathematics and its application, comet theories", "mathematics and its application, secret theories"
"mathematics and its application, set theories" » "mathematics and its application, set theory"

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