diff --git a/src/transliteration/domain/markup.ts b/src/transliteration/domain/markup.ts
index 9debcd42e..fb1a3fcbf 100644
--- a/src/transliteration/domain/markup.ts
+++ b/src/transliteration/domain/markup.ts
@@ -15,7 +15,7 @@ export interface UrlPart {
 
 export interface LanguagePart {
   readonly type: 'LanguagePart'
-  readonly language: 'AKKADIAN' | 'SUMERIAN' | 'EMESAL'
+  readonly language: 'AKKADIAN' | 'SUMERIAN' | 'EMESAL' | 'HITTITE'
   readonly tokens: readonly Token[]
 }