We have already cited some examples from this shia book regarding visitation of shrines at our blog.
In the introduction to his book (p4), author ibn Qawlaveyh al-Qummi said:
وقد علمنا أنّا لا نحيط بجميع ما روي عنهم في هذا المعنى ولا في غيره ، لكن ما وقع لنا من جهة الثّقات من أصحابنا ـ رحمهم الله [برحمته] ـ ولا أخرجت فيه حديثاً روي عن الشُّذاذ من الرِّجال
We realize we cannot cover all that which has been transmitted from them (imams) on this subject [the salutations at the shrines], nor on any other issue, except that which has been related to us by reliable [transmitters] from our companions – may Allah forgive them by His Rahmat. I have not cited a tradition in it [the book] which has been transmitted by reporters who are rarely mentioned (shudhdhadh).
Thus, all of the 388 transmitters who appear in Ibn Qawlawayh’s work are authenticated by this inference.