TypeScript definition file correction

I think columns need correction for GridColumn interface:

interface GridColumn {

aggregates?: any;

attributes?: any;

columns?: any; //I think this should be GridColumn[] not any

command?: GridColumnCommandItem[];

encoded?: boolean;

field?: string;

filterable?: boolean|GridColumnFilterable;

footerAttributes?: any;

footerTemplate?: string|Function;

format?: string;

groupable?: boolean;

groupHeaderTemplate?: string|Function;

groupFooterTemplate?: string|Function;

headerAttributes?: any;

headerTemplate?: string|Function;

hidden?: boolean;

locked?: boolean;

lockable?: boolean;

minScreenWidth?: number;

sortable?: boolean|GridColumnSortable;

template?: string|Function;

title?: string;

width?: string|number;

values?: any;

menu?: boolean;

}