The following command will list the different versions available based on a filter string. You need to use the Visual Studio Package Manager Console window.
Get-Package -ListAvailable -Filter MyFilter -AllVersions
Get-Package -ListAvailable -Filter AspNet.ScriptManager.jQuery -AllVersions
//to install a specific version
Install-Package The.Package.Name -Version 1.2.0
Install-Package AspNet.ScriptManager.jQuery -Version 1.9.1
Install-Package EntityFramework -Version 5.0.0