function CheckFoundUsSelect( control )
{
var selectedValue = control.options[ control.selectedIndex ].value;

    switch( selectedValue )
    {
        // Journal
        case "Zeitschrift":
            document.getElementById( 'FoundUs_Placeholder' ).style.display = "none";
            document.getElementById( 'FoundUs_JournalName' ).style.display = "";
            document.getElementById( 'FoundUs_LetterType' ).style.display  = "none";
            document.getElementById( 'FoundUs_Event' ).style.display  = "none";
            document.getElementById( 'FoundUs_Internet' ).style.display  = "none";
            break;
        // Letter
        case "Anschreiben":
            document.getElementById( 'FoundUs_Placeholder' ).style.display = "none";
            document.getElementById( 'FoundUs_JournalName' ).style.display = "none";
            document.getElementById( 'FoundUs_LetterType' ).style.display  = "";
            document.getElementById( 'FoundUs_Event' ).style.display  = "none";
            document.getElementById( 'FoundUs_Internet' ).style.display  = "none";
            break;
        // Letter
        case "Veranstaltung":
            document.getElementById( 'FoundUs_Placeholder' ).style.display = "none";
            document.getElementById( 'FoundUs_JournalName' ).style.display = "none";
            document.getElementById( 'FoundUs_LetterType' ).style.display  = "none";
            document.getElementById( 'FoundUs_Event' ).style.display  = "";
            document.getElementById( 'FoundUs_Internet' ).style.display  = "none";
            break;
        // Letter
        case "Internet":
            document.getElementById( 'FoundUs_Placeholder' ).style.display = "none";
            document.getElementById( 'FoundUs_JournalName' ).style.display = "none";
            document.getElementById( 'FoundUs_Event' ).style.display  = "none";
            document.getElementById( 'FoundUs_Internet' ).style.display  = "";
            break;
        default:
            // do nothing
            document.getElementById( 'FoundUs_Placeholder' ).style.display = "";
            document.getElementById( 'FoundUs_JournalName' ).style.display = "none";
            document.getElementById( 'FoundUs_LetterType' ).style.display  = "none";
            document.getElementById( 'FoundUs_Event' ).style.display  = "none";
            document.getElementById( 'FoundUs_Internet' ).style.display  = "none";
            break;
    }
}