protected IEnumerable <TPage> GetPagesOfMultipleTypes(
IEnumerable <string> types,
SiteCulture culture,
Action <MultiDocumentQuery>?filter = default)
{
MultiDocumentQuery query = GetQueryForMultipleTypes(types, culture, filter);
return(query
.GetEnumerableTypedResult()
.Select(page => page as TPage)
.Where(page => page != null) !);
}