public ExternalName getExternalName(String nameName, String sheetName, int externalWorkbookNumber) {throw new IllegalStateException("XSSF-style external names are not supported for HSSF");}

public ExternalName GetExternalName(String nameName, String sheetName, int externalWorkbookNumber){throw new InvalidOperationException("XSSF-style external names are not supported for HSSF");}
