diff --git a/commonItems.UnitTests/Linguistics/StringExtensionsTests.cs b/commonItems.UnitTests/Linguistics/StringExtensionsTests.cs
index 2964b081..3c73d91c 100644
--- a/commonItems.UnitTests/Linguistics/StringExtensionsTests.cs
+++ b/commonItems.UnitTests/Linguistics/StringExtensionsTests.cs
@@ -1,7 +1,10 @@
 using commonItems.Linguistics;
 using Csv;
+using FluentAssertions;
+using System;
 using System.IO;
 using System.Linq;
+using System.Net;
 using Xunit;
 
 namespace commonItems.UnitTests.Linguistics;
@@ -181,6 +184,13 @@ public class StringExtensionsTests {
 	[InlineData("Mcif", "Mcifi")]
 	[InlineData("Maqomo", "Maqomo")]
 	[InlineData("Frej", "Frejite")]
+	[InlineData("Trelew", "Trelewense")]
+	[InlineData("Nanaimo", "Nanaimoite")]
+	[InlineData("Envigado", "Envigadeño")]
+	[InlineData("Chigorodó", "Chigorodoseño")]
+	[InlineData("San Bernardo", "San Bernardino")]
+	[InlineData("Encantado", "Encantense")]
+	[InlineData("Lincoln", "Lincolnite")]
 	
 	// adjectives relying on rewrite rules
 	[InlineData("Armenia Maioris", "Greater Armenian")]
@@ -472,6 +482,35 @@ public void CorrectAdjectivesAreGeneratedForNamesFromCsv(string csvFilePath) {
 		}
 	}
 
+	[Fact]
+	public void AdjectiveRuleExistsForEveryCountryAndMajorCityInTheWorld() {
+		var csvUrl = "https://datahub.io/core/world-cities/r/world-cities.csv";
+		var csv = new WebClient().DownloadString(csvUrl);
+		var cities = CsvReader.ReadFromText(csv)
+			.Select(line => line[0])
+			.Where(city => !string.IsNullOrEmpty(city) && !city.StartsWith("Zürich (Kreis"))
+			.Distinct()
+			.ToList();
+		
+		var countries = CsvReader.ReadFromText(csv)
+			.Select(line => line[1])
+			.Where(country => !string.IsNullOrEmpty(country))
+			.Distinct()
+			.ToList();
+
+		var output = new StringWriter();
+		Console.SetOut(output);
+
+		foreach (var city in cities) {
+			_ = city.GetAdjective();
+		}
+
+		foreach (var country in countries) {
+			_ = country.GetAdjective();
+		}
+		output.ToString().Should().NotContain("No matching adjective rule found");
+	}
+
 	[Theory]
 	// ReSharper disable StringLiteralTypo
 	[InlineData("Vilath#?!", "Vilathian")]
diff --git a/commonItems/Linguistics/adjective_rules.txt b/commonItems/Linguistics/adjective_rules.txt
index ec8b5a0d..af3ac44d 100644
--- a/commonItems/Linguistics/adjective_rules.txt
+++ b/commonItems/Linguistics/adjective_rules.txt
@@ -191,6 +191,7 @@
 {"*anon", "*anese"}, // Lebanon
 {"*anya", "*anyan"}, // Netanya
 {"*aras", "*arentine"}, // Taras
+{"*ardo", "*ardino"}, // San Bernardo
 {"*aros", "*arian"}, // Paros
 {"*atar", "*atari"}, // Qatar
 {"*atte", "*atian"}, // Ville Platte
@@ -235,6 +236,7 @@
 {"*etus", "*esian"}, // Miletus
 {"*ford", "*fordian"}, // Bedford
 {"*furt", "*furter"}, // Frankfurt
+{"*gado", "*gadeño"}, // Envigado
 {"*gamo", "*gamasque"}, // Bergamo
 {"*gano", "*ganese"}, // Lugano
 {"*gana", "*ganite"}, // Telangana
@@ -341,6 +343,7 @@
 {"*[c]cis", "*[c]cidian"}, // Chalcis
 {"*[c]nai", "*[c]naite"}, // Chennai
 {"*[v]ris", "*[v]risian"}, // Marmaris
+{"*[v]ado", "*[v]ense"}, // Encantado
 {"*[c]ver", "*[c]ver"}, // Denver
 {"*[v]ver", "*[v]verian"}, // Hanover
 
@@ -407,6 +410,7 @@
 {"*ice", "*icean"}, // Nice
 {"*ier", "*ieran"}, // Napier
 {"*iev", "*ievan"}, // Kiev
+{"*imo", "*imoite"}, // Nanaimo
 {"*ing", "*ingite"}, // Kuching
 {"*ini", "*inian"}, // Leontini
 {"*inz", "*inzer"}, // Linz
@@ -548,6 +552,7 @@
 {"*ce", "*cian"}, // Thrace
 {"*co", "*can"}, // Morocco
 {"*de", "*dean"}, // Cape Verde
+{"*dó", "*doseño"}, // Chigorodó
 {"*du", "*dunite"}, // Ordu
 {"*eh", "*ehi"},
 {"*ej", "*ejite"},
@@ -557,7 +562,8 @@
 {"*én", "*enés"}, // Jaén
 {"*eo", "*ean"}, // Bengeo
 {"*er", "*erite"}, // Casper
-{"*es", "*ian"}, // Maldives
+{"*es", "*ian"}, // Maldives,
+{"*ew", "*ewense"}, // Trelew
 {"*ge", "*ginian"}, // Carthage
 {"*gh", "*ghian"}, // Middlesbroughian
 {"*gk", "*gkan"},
@@ -581,6 +587,7 @@
 {"*ku", "*kuvian"}, // Baku
 {"*ld", "*ldian"}, // Chesterfield
 {"*ll", "*llese"}, // Marshall
+{"*ln", "*lnite"}, // https://en.wikipedia.org/wiki/Lincoln,_Nebraska
 {"*lo", "*lonian"}, // Buffalo
 {"*lu", "*lan"}, // Honolulu
 {"*me", "*man"}, // Rome
diff --git a/commonItems/commonItems.csproj b/commonItems/commonItems.csproj
index 39201c66..d89cccf7 100644
--- a/commonItems/commonItems.csproj
+++ b/commonItems/commonItems.csproj
@@ -6,7 +6,7 @@
 
     <GeneratePackageOnBuild>False</GeneratePackageOnBuild>
     <PackageId>PGCG.$(AssemblyName)</PackageId>
-    <Version>8.4.1</Version>
+    <Version>8.4.2</Version>
     <Authors>PGCG</Authors>
     <PackageProjectUrl>https://github.com/ParadoxGameConverters/commonItems.NET</PackageProjectUrl>
     <RepositoryUrl>https://github.com/ParadoxGameConverters/commonItems.NET</RepositoryUrl>