The easiest way is to look at the publication information.
An ebook will have a publishing location and company just like a physical book -
Sanders, P. (1996). Bullying (What do you know about). Brookfield, CT: Copper Beech
Books. http://search.ebscohost.com/login.aspx?direct=true&scope=site&db=nlebk&db
An article will have a volume number and possible an issue number -
Shea, M., Wang, C., Shi, W., Gonzalez, V., & Espelage, D. (2016). Parents and teachers’
perspectives on school bullying among elementary school-aged Asian and Latino
immigrant children. Asian American Journal Of Psychology, 7(2), 83-96.
doi:10.1037/aap0000047