EDIT

    ToOneRelatedEntityCombobox<Reference> citation = new ToOneRelatedEntityCombobox<Reference>(null, Reference.class);

    TextField citationMicroReference = new TextFieldNFix();

    TextField ruleConsidered = new TextFieldNFix();

    public NomenclaturalStatusRow() {

        citation.setNestedButtonStateUpdater(new ToOneRelatedEntityButtonUpdater<Reference>(citation));

        citationMicroReference.setWidth(200, Unit.PIXELS);

        ruleConsidered.setWidth(200, Unit.PIXELS);

    }

    /**

                type,

                citation,

                citationMicroReference,

            };

        addAll(Arrays.asList(components));

        return components;

            "type",

            "citation",

            "citationMicroReference",

            });

        return visibleFields;

    }