My professor told me to critically summarize and evaluate each work (for its premise, methodology, and conclusion) I am including in my Literature Review. I understand that I should provide in-text citations when mentioning the source; however, I'm not sure that I should write an in-text citation for every sentence describing how the study was conducted.
Ex: A study by Lina Aldén and Mats Hammarstedt examined cohorts of refugees who migrated to Sweden between the years 2005 and 2007, tracking them longitudinally up until 2012. Data used in the study was obtained from the LISA database at Statistics Sweden, which included information about refugees national origin, age, gender, educational attainment, number of children, employment status, and taxable income, all of which are influential in determining migrants economic contribution. The results from their analyses reveal that the average refugee had public sector net costs of SEK 142,250 (13,714€) during the first year of residency (Citation). After seven years, this cost was halved (Citation).
I added citations to the last two sentences where I mention the results of the study, but I am confused as to whether I need to add citations following each sentence describing the study. This will be in MLA if that's relevant to the question.