Hi Nilma,
Here is a link to the Canadian Journal of Higher Education, where there are a number of articles related to Teaching Assistants in the Canadian context:
Kindly,
Michelle Nilson, Ph.D. (She/Her/Hers)
Associate Professor, Faculty of Education, Simon Fraser University
Director, Centre for the Study of Educational Leadership and Policy (CSELP), https://www.sfu.ca/cselp.html
President, Canadian Society for the Study of Higher Education (CSSHE), https://csshe-scees.ca/
SFU acknowledges the Squamish, Musqueam, Tsleil-Waututh, Katzie and Kwikwetlem peoples on whose traditional territories our three campuses stand.