diff --git a/globalize/globalize-tests.ts b/globalize/globalize-tests.ts
index 5174f90f9..3d599a611 100644
--- a/globalize/globalize-tests.ts
+++ b/globalize/globalize-tests.ts
@@ -33,7 +33,9 @@ Globalize.parseDate("15 Jun 2012", ["dd MMM yyyy"]);
 Globalize.culture("fr");
 Globalize.parseDate("1/2/2003"); 
 
+Globalize.addCultureInfo({ numberFormat: { billionZeroes: 12 } });
 Globalize.addCultureInfo("fr", { numberFormat: { billionZeroes: 12 } });
+Globalize.addCultureInfo("de-DE", "de", { numberFormat: { billionZeroes: 12 } });
 
 //Globalize.culture().calendar = Globalize.culture().calendars.SomeOtherCalendar;
 //Globalize.culture().calendar = Globalize.culture().calendars.standard;
diff --git a/globalize/globalize.d.ts b/globalize/globalize.d.ts
index da17957f1..91f991833 100644
--- a/globalize/globalize.d.ts
+++ b/globalize/globalize.d.ts
@@ -100,18 +100,20 @@ interface GlobalizeCultures {
 
 interface GlobalizeStatic {
     cultures: GlobalizeCultures;
-    init(cultureSelector: string);
+    init(cultureSelector: string): GlobalizeStatic;
     cultureSelector: string;
 
     culture(): GlobalizeCulture;
     culture(cultureSelector: string): GlobalizeCulture;
     culture(cultureSelector: string[]): GlobalizeCulture;
 
-    addCultureInfo(cultureName: string, baseCultureName, info?);
-    findClosestCulture(cultureSelector: string);
+    addCultureInfo(cultureName: string, baseCultureName: string, info: Object): void;
+    addCultureInfo(cultureName: string, info: Object): void;
+    addCultureInfo(info: Object): void;
+    findClosestCulture(cultureSelector: string): GlobalizeStatic;
     format(value: number, format: string, cultureSelector?: string);
     format(value: Date, format: string, cultureSelector?: string);
-    localize(key: string, cultureSelector?: string);
+    localize(key: string, cultureSelector?: string): string;
 
     parseDate(value: string, format?: string, cultureSelector?: string): Date;
     parseDate(value: string, formats?: string[], cultureSelector?: string): Date;