12988 - बारह नौ सौ अठासी , इसके नखरे हैं नवाबी ! - Keshav Saxena

AFAIK 1964 is the year when North Bengal exp was renamed as Darjeeling mail, not the year of "inauguration" of Darjeeling mail. The year of introduction of Darjeeling mail should be year of introduction of North Bengal exp. North Bengal exp used to run well before 1964 also although i am not sure about the exact year of introduction

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