Experimental and numerical results of optical preamplification in a laser Doppler anemometer receiving head. - Helmut Többen; Miroslav Kárbsek (IEEE Trans. Instrum. Meas., 2000)

Symbology Development for a 3D Conformal Synthetic Vision Helmet-Mounted Display for Helicopter Operations in Degraded Visual Environment. - Patrizia Knabl; Helmut Többen (HCI (16), 2013)