declare namespace Ext {
    export namespace mixin {
        export interface ContainerConfig {
            referenceHolder?: boolean;
        }

        export class Container extends Ext.Mixin  {
            public isContainer?: boolean;
            public getReferenceHolder(): void;
            public getReferences(): object;
            public lookup(key?: string): Ext.Component;
            public lookupReference(key?: string): Ext.Component;
            public setReferenceHolder(): void;
        }
    }
}