Schweingruber, F. H. (2007). Tree-ring measurements of Picea engelmannii (Engelmann spruce) from sample BITTER-131. PANGAEA.
Citazione stile Chigago Style (17a edizione)Schweingruber, Fritz Hans. Tree-ring Measurements of Picea Engelmannii (Engelmann Spruce) from Sample BITTER-131. PANGAEA, 2007.
Citatione MLA (9a ed.)Schweingruber, Fritz Hans. Tree-ring Measurements of Picea Engelmannii (Engelmann Spruce) from Sample BITTER-131. PANGAEA, 2007.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.