First use of the term "Hindustan"

I placed this query with H-Net that when was the word Hindustan used for the first time.

I received following answer: It is not clear if Dr. Jodi Singh or Dr. Sharma have the usage in theGuru Granth Sahib identified as a 'first use' by an Indian writer, orabsolute first use. A quick glance at the _Encyclopedia of Islam_ articleon "Hind" in Volume 3: 404-434 includes references to "Hindustan" beingemployed in the early 13th century CE. But I encourage others to offerother specifics.
It was an answer by Frank Conlon, Professor Emeritus, Washington University.

The second response was as follows:
the term "Hindustan" was known to the Muslim Persians at least sincethe early 11th century (see the just published entry "Hindu" in theEncyclopaedia Iranica, and the soon forthcoming various articles on"India"). At that time it was known to the Persian poet Ferdowsi,who referred to "Hendustan" in the "Shah-Nameh" or "Book of Kings".Best,Dr. Christoph W. Marcinkowski:

The third response was this:
The earliest use of the word is in a third century inscription of theSasanian king Shahpur I: it mentions to hndstan, 'stan' being a MiddlePersian suffix.The reference is to the north western part of India.D N JhaProfessor of HistoryUniversity of Delhi

It was a great experience to learn about this fact. I thank it to www and computers. Had I tried it on my own, I do not think that I have found a better answer or anything near to it.

But it also left me with a sad feeling.

I placed this query with an American scholar. It was mere a query though the urge to seek answer to this question was equally important. The surprising thing was that I received an authoritative answer. Among the answers, I also received an answer from my native scholar who is person of great standing in the field of history. He is also presently the chairman of the coming IHC. I directed one of my query to him. I have not received any confirmation from him.

It left me sad. I am just thinking that how these western scholars work for their field. But in my country, there is so much talk of Guru, sharing of knowledge, the Shrutis and Samritis but our scholars do not feel it civilized to answer the queries of their fellow seeker.

It is just an experience which hides itself numerous other thoughts and feeling. But I am just disenchanted to some extend.

On the other hand, it also gives me encouragement to continue with my efforts of seeking knowledge.