function submit_search(op,series,id,dropdown_type,search_type) {
                var index = op.selectedIndex;
                var criteria = op.options[index].value;
                if(criteria != "") {
                        if(dropdown_type == "search") {
                        top.location =
                        "static-"+id+"?type="+search_type+"&search=advanced&series="+series+"&criterias=" + criteria;
                        } else if(dropdown_type == "goto_bookpage") {
                                top.location = "book-" + criteria;
                        }
                }

        }