  The purpose of this paper is to analyze the capabilities, functionalities and
appropriateness of Altmetric.com as a data source for the bibliometric analysis
of books in comparison to PlumX. We perform an exploratory analysis on the
metrics the Altmetric Explorer for Institutions platform offers for books. We
use two distinct datasets of books: the Book Collection included in
Altmetric.com and the Clarivate's Master Book List, to analyze Altmetric.com's
capabilities to download and merge data with external databases. Finally, we
compare our findings with those obtained in a previous study performed in
PlumX. Altmetric.com combines and orderly tracks a set of data sources combined
by DOI identifiers to retrieve metadata from books, being Google Books its main
provider. It also retrieves information from commercial publishers and from
some Open Access initiatives, including those led by university libraries such
as Harvard Library. We find issues with linkages between records and mentions
or ISBN discrepancies. Furthermore, we find that automatic bots affect greatly
Wikipedia mentions to books. Our comparison with PlumX suggests that none of
these tools provide a complete picture of the social attention generated by
books and are rather complementary than comparable tools.
