The researchers will be monitoring the study subjects over a period of several years in order to document their mental health and the stress factors to which they are exposed over time. (sciencedaily.com)
If sustained over a period of several years, such a temperature decrease could be sufficient to trigger an ice age!. (realclimate.org)
The recipes and their final formulations have been developed over a period of several years to build solid commercial products. (fooddrink-magazine.com)