Keep Right/090 motorways without ref

Message: This way is tagged as motorway and therefore needs a ref, nat_ref or int_ref tag

This error shows all ways tagged as highway=motorway without ref=* on way or relation.

Continent	World	Africa	America-Canada	America-Central	America-South	America-US	Asia	Australia-Oceania	Europe
20150907	53,344	1,193	364	1,476	1,981	3,671	43,006	406	1,246
20141230	48,438	1,025	334	1,172	2,204	3,622	38,463	448	1,169
20140423	48,399	1,297	352	1,548	2,532	3,714	37,135	451	1,366
20131003	51,887	1,380	336	1,516	2,944	4,978	38,820	470	1,443
20130710	52,814	1,228	330	1,489	2,969	4,794	40,228	370	1,406
20130116	51,468	1,216	362	1,515	2,684	5,384	38,400	459	1,448
20121112	49,052	1,093	361	1,432	2,611	5,443	35,974	678	1,460
20121015	48,484	1,099	389	1,562	2,535	5,453	35,231	725	1,490
20120926	47,407	1,034	367	1,455	2,664	5,185	34,471	764	1,467
20120917	47,311	1,114	366	1,473	2,664	5,121	33,251	1,863	1,459
20120913	47,196	1,114	368	1,473	2,660	5,119	33,023	1,862	1,577