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In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.

Passage: Perhaps influenced by van Eyck's Madonna in the Church, Lochner closely detailed the fall and gradient of light. According to the art historian Brigitte Corley, the clothes of "protagonists change their hues in delicate reaction to the influx of light, reds being transformed through a symphony of pink tonalities to a dusty greyish white, greens to a warm pale yellow, and lemon shading through oranges to a saturated red". Lochner employed the notion of supernatural illumination not just from van Eyck, but also from von Soest's Crucifixion, where light emanating from Christ dissolves around John's red robe, as yellows rays eventually become white. There is a real possibility that a number of the faces of saints are modelled on historical persons, i.e. as donor portraits of the commissioners and their wives. Figures fitting this theory include St Ursula and St Gereon panels from the City Saints altarpiece.Unlike the painters in the Low Countries, Lochner was not so concerned with delineating perspective; his pictures are often set in shallow space, while his backgrounds give little indication of distance and often dissolve into solid gold. Thus, and given his harmonious colour schemes, Lochner is usually described as one of the last exponents of the International Gothic. This is not to say his paintings lack contemporary northern sophistication; his arrangements are often innovative. The worlds he paints are hushed, according to Snyder, achieved with the symmetry of subdued use of colour and the often repeated stylistic element of circles. Angels form circles around the heavenly figures; the heavenly figures' heads are highly circular and they wear round haloes. According to Snyder, the viewer is slowly "drawn into empathy with the revolving forms".Because of the paucity of surviving attributed works, it is difficult to detect any evolution in Lochner's style. Art historians are unsure if his style became progressively more or less influenced by Netherlandish art. Recent dendrochronological examination of attributed works indicate that his development was not linear, suggesting that the more advanced Presentation in the Temple is of 1445, predating the more Gothic Saints panels now divided between London and Cologne.
Output:
What are the names of the two saints who are among the number of faces for which there is a real possibility they are modelled on historical persons?