dear brother, indo pak history in my experience is a tricky subject as you cannot just pass by quoting a few historians. one must be able to fully understand the geo political environment of the whole region/time period to fully understand an event.only then wud u be able to give your analysis of the sitation.
my humble suggestion would be that go for genuine authors like v.d mahajan,stanley lane poole and prof.habib etc.though some times they tend to be a lil bit biased but with thorugh study of various authors you would eventally be able to grasp the idea and can than sieve facts from fabrication.
for example ,muslim conquest requires that one should be fully aware of the dynamics of the change in caliphate,muslim military campaigns in the adjoining areas of persia and so on...while stdying ghaznavi we need to find out the reasons behind rise of trks and saljuks in that era,the origin and logic behind rise of independent principalities etc etc.books like k.ali do not give a comprehensive and satisfying logic for all this.so better focus on finding facts on yor own through various books and wikipedia.

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