KALBARCZYK, Robert. “The Application of the Cluster Analysis in Recognizing Weather Patterns Conducive to Large and Small Crops of Mid-Late Onion Cultivars (Allium Cepa L.) in Poland”. Notulae Botanicae Horti Agrobotanici Cluj-Napoca 38, no. 1 (June 15, 2010): 100-108. Accessed October 19, 2019. https://notulaebotanicae.ro/index.php/nbha/article/view/3591.