Article/Book Citation Impact: The academic impact of particular works, such as journal articles, conference proceedings, and books, can be measured by the number of times they are cited by other works
Journal Citation impact: The impact of particular academic journals can be measured by the number of times their articles are cited and where they are cited.
Researcher Citation impact: The number of works a researcher has published and the number of times these works have been cited can be an indicator of the academic impact of an individual researcher