New paper

Spielmann F.M., Kitz F., Hammerle A., Gerdel K., Alberti G., Delle Vedove G., Ibrom A., Karl T., Kolle O., Migliavacca M., El-Madany T.S., Moreno G., Peressoti A., Wohlfahrt G. (2019) Gross primary productivity of four European ecosystems constrained by joint CO2 and COS flux measurements. Geophysical Research Letters, in press.