query string--multiple parameter

Between/ And paramenter throgh query string
Can any one help me passing parameter through querystring
I need to pass querystring parameter on "click_submitt"
 year = Between "startyear and end year"
and value for radiobutton and country
 from main.aspx.cs
  int styear = Convert.ToInt32(ddlyr.SelectedValue);
            int endyear = Convert.ToInt32(ddlyr.SelectedValue);
             String type = RBl1.SelectedValue;
  String country= ddlcountry.selectedvaue;
I also need to check Start year should be less than end year
How i should address theses parameter in detail.aspx and show results in gridview
Pl. help
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