diagram usually supported by three main structures: the branches of a stylised tree, a palace, or lotus flower and lion throne. The support depends on the lineage and the liturgical text the painting is based on. When the support is a tree, it is often referred to as a "wish-fulfilling tree" (Wylie: dpag bsam gyi shing). In A Shrine for Tibet, Marylin M. Rhie and Robert A. F. Thurman assert that the depiction of the Refuge Assembly in the form of a tree "developed from the ancient tradition of the Buddha being born under an ashoka tree, attaining enlightenment under a pipal or Bodhi Tree, and passing away from his coarse material body under two sal trees". Four main schools of Tibetan Buddhism Gelug The configuration of the earliest known Refuge Tree paintings appear to be based on the 17th century Lama Chopa text by the 1st Panchen Lama, Khedrup Gelek Pelzang of the Gelug Tradition. In this text, he described the Field of Accumulation in a configuration on the peak of a tree with Shakyamuni Buddha representing the Root Lama as the main figure. Later Gelug paintings also feature the founder of the Gelug sect, Je Tsongkapa as the central figure. In both cases, as Jackson and Jackson describe, the central figure is at the pinnacle of the tree "surrounded by descending concentric rows of exalted beings". These rows consist of eight classes of beings: Gurus, Yidams, Buddhas, Bodhisattvas, Pratyekabuddhas, Sravakas and Sthaviras, Dakas, and Dharmapalas. A popular Gelug structure of the Refuge Tree composition also includes three separate assemblies of teachers above the main figure. In this case, according to Jackson and Jackson:the teaching lineage of the tantric empowerments and practices constitute[s] the central group. On the main figure's right there [is] the "Lineage of the Vast Conduct", the lineage of the Yogacara Mahayana descending from Maitreyanatha and Asanga. On the other side [is] the "Lineage of the Profound View", the Madhyamaka tradition coming down through Manjusri and Nagarjuna. Karma Kagyu The Karma Kagyu sect of Tibetan Buddhism developed another form of tree structure for their objects of "Refuge". The Karma Kagyu Refuge Field was described in the form of a five-branched tree by 9th Karmapa, Wangchug Dorje in his 16th-century texts Lhancig Kyejor Tri (Wylie: lhan cig skyes sbyor khrid) and Paglam Dropa’I Shingta (Wylie: ‘phags lam bgrod pa’I shing rta). Based on known examples of Karma