IfcDoc.FormatOWL.createListClass C# (CSharp) Method

        public string createListClass(string defined)
        {
            StringBuilder sb = new StringBuilder();

            if (!listPropertiesOutput.Contains(defined) && defined.StartsWith("ifc"))
            {
                listPropertiesOutput.Add(defined);

                sb.AppendLine(defined + "_EmptyList");
                sb.AppendLine("\trdf:type owl:Class ;");
                sb.AppendLine("\trdfs:subClassOf list:EmptyList, " + defined + "_List" + " .");
                sb.AppendLine();

                sb.AppendLine(defined + "_List");
                sb.AppendLine("\trdf:type owl:Class ;");
                sb.AppendLine("\trdfs:subClassOf list:OWLList ;");
                sb.AppendLine("\trdfs:subClassOf");
                sb.AppendLine("\t\t[");
                sb.AppendLine("\t\t\trdf:type owl:Restriction ;");
                sb.AppendLine("\t\t\towl:onProperty list:hasContents ;");
                sb.AppendLine("\t\t\towl:allValuesFrom " + defined);
                sb.AppendLine("\t\t] ;");
                sb.AppendLine("\trdfs:subClassOf");
                sb.AppendLine("\t\t[");
                sb.AppendLine("\t\t\trdf:type owl:Restriction ;");
                sb.AppendLine("\t\t\towl:onProperty list:isFollowedBy ;");
                sb.AppendLine("\t\t\towl:allValuesFrom " + defined + "_List");
                sb.AppendLine("\t\t] ;");
                sb.AppendLine("\trdfs:subClassOf");
                sb.AppendLine("\t\t[");
                sb.AppendLine("\t\t\trdf:type owl:Restriction ;");
                sb.AppendLine("\t\t\towl:onProperty list:hasNext ;");
                sb.AppendLine("\t\t\towl:allValuesFrom " + defined + "_List");
                sb.AppendLine("\t\t] .");
                sb.AppendLine();
            }

            return sb.ToString();
        }