This is the 6078th most frequent Russian word.
специалистам
"To specialists" (dative plural of "специалист").
In this sentence, 'специалистам' is the dative plural form of 'специалист,' used to indicate the entities to whom the action is directed (to specialists).
Мы обратились к специалистам для решения этой проблемы.
We turned to specialists to solve this problem.
Here, 'специалистам' indicates the target audience for whom the books are meant, using the dative plural form to convey purpose.
Эти книги предназначены для специалистов в области биологии.
These books are intended for specialists in the field of biology.
In this usage, 'специалистам' again appears in the dative plural form, indicating the recipients of the information.