Is this journal peer-reviewed? Where is it indexed? What are the credentials of the editorial boards?
Where is this journal ranked in its research field(s)?
Is this conference peer-reviewed? Where are the proceedings indexed? What are the credentials of the organisers/keynote speakers?
Where is the conference ranked in its field(s)?
What are the quality or impact measures of the conference proceedings?
Evaluating the quality of monographs/monograph publishers can be challenging, as not all books and book chapters are indexed in the major databases. Guidance from your supervisors and colleagues is extremely important.
To evaluate the scholarly quality and impact of a monograph (e.g., a book), you could consider:
Is the book peer-reviewed? What are the credentials of the editors and publishers?
Is the publisher considered a high impact or quality publisher?