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Another way to change the current view is to use the small calendar from the left sidebar. Click on the small arrows to change the month and select a date to see the corresponding events. To see the events from a date range, click on the start date and drag it to the end date. Note that this only works for short periods of time.
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Google Calendar has two useful shortcuts that let you easily move between periods of time: p (previous date range) and n (next date range). To see the events from a certain month in the past, click on "Today", go to the month view and repeatedly press p. Alternatively, type a date in the search box and click on "Search my calendars".
{ via Google Calendar Group }