diff --git a/docs/ApiValidationRules.md b/docs/ApiValidationRules.md
index c080ae0..0e6b46f 100644
--- a/docs/ApiValidationRules.md
+++ b/docs/ApiValidationRules.md
@@ -112,7 +112,7 @@ Usually the "Z" is missing at the end indicating local time.
 
 #### Required fields
 
-* eta / etd (depending on value of type: 1: eta, 2: etd, 3: both)
+* eta / etd (depending on value of type: 1: eta, 2: etd, 3: etd)
 * type
 * ship_id
 * arrival_berth_id / departure_berth_id (depending on type, see above)