diff --git a/data/test-cases b/data/test-cases
index 0423552..fe9ea99 100644
--- a/data/test-cases
+++ b/data/test-cases
@@ -35,6 +35,7 @@ o, p: a/b//d
 o, p: a(r)
 o, p: a/b (r)
 o, p: e123-E124a
+o, p: E123/E124
 p\na, b\n\nq\nc
 # amounts
 tomaat (30%)
diff --git a/lib/food_ingredient_parser/strict/grammar/list.treetop b/lib/food_ingredient_parser/strict/grammar/list.treetop
index 7abad0a..6e82bc8 100644
--- a/lib/food_ingredient_parser/strict/grammar/list.treetop
+++ b/lib/food_ingredient_parser/strict/grammar/list.treetop
@@ -8,13 +8,9 @@ module FoodIngredientParser::Strict::Grammar
       contains:(ingredient ( ws* ';' ws* ingredient )+ ( ws+ and ws+ ingredient )? )      <ListNode> /
       contains:(ingredient ( ws* ',' ws* ingredient )+ ( ws+ and ws+ ingredient )? )      <ListNode> /
       contains:(ingredient ( ws* '.' ws* ingredient )+ ( ws+ and ws+ ingredient )? )      <ListNode> /
-      list_e_number /
-      contains:(ingredient ( ws+ and ws+ ingredient )? )                                  <ListNode>
-    end
-
-    rule list_e_number
       contains:(ingredient_simple_e_number ( ws* '/'  ws* ingredient_simple_e_number )+ ) <ListNode> /
-      contains:(ingredient_simple_e_number ( ws* dash ws* ingredient_simple_e_number )+ ) <ListNode>
+      contains:(ingredient_simple_e_number ( ws* dash ws* ingredient_simple_e_number )+ ) <ListNode> /
+      contains:(ingredient ( ws+ and ws+ ingredient )? )                                  <ListNode>
     end
   end
 end
diff --git a/lib/food_ingredient_parser/strict/grammar/list_coloned.treetop b/lib/food_ingredient_parser/strict/grammar/list_coloned.treetop
index be71bc4..1fdd8f5 100644
--- a/lib/food_ingredient_parser/strict/grammar/list_coloned.treetop
+++ b/lib/food_ingredient_parser/strict/grammar/list_coloned.treetop
@@ -17,6 +17,7 @@ module FoodIngredientParser::Strict::Grammar
     end
 
     rule list_coloned_inner_list
+      contains:( ingredient_simple_e_number ( ws* '/'  ws* ingredient_simple_e_number )+ ) <ListNode> /
       contains:( ingredient_simple_e_number ( ws* dash ws* ingredient_simple_e_number )+ ) <ListNode> /
       contains:( ingredient ( ws* ',' ws* ingredient )* ) <ListNode>
     end