我如何引用另一个(打开或关闭的)工作簿，并在VBA中拉回值?——Excel 2007

Basically I need to gather a fair few figures from another workbook (Which is found and can be opened by a UserForm, therefore the location and names are variable). I need to use VBA for this as I also need to populate a chart with this data. I would prefer to not have to open the other workbook in order to do it, but if it is far easier then its OK.Basically I need to gather a fair few figures f