for (let i: number = horizontalIndex + 1; i < this.graphicalMusicSheet.VerticalGraphicalStaffEntryContainers.length; i++) {
            if (this.graphicalMusicSheet.VerticalGraphicalStaffEntryContainers[i].StaffEntries[verticalIndex]) {
                return this.graphicalMusicSheet.VerticalGraphicalStaffEntryContainers[i].StaffEntries[verticalIndex];
            }
        }