Question: When was the painter of Sunflowers discovered?
About the article "Sunflowers (Van Gogh series)", section "The Paris "Sunflowers"".

Candidate passages:
Applications of grain drying.
Sunflower drying.
For different types of sunflowers, the preservation moisture content is different.
Oilseed sunflowers are better dried to 9 percent moisture content, while bird seed sunflowers are 10 percent moisture content.
Compared to corn drying, sunflowers are more easily to be dried and kept in safe storage.
What's more, high temperature may not have adverse effect on sunflowers kernel, which may be the reason of the fatty acid composition.
There was no evidence of damage when air was heated up to 220°F in drying.
However, fine hairs and fibers on the seed coat of sunflowers may cause fire hazard.
It is suggested that remove the flaming particles first when hitting the sunflowers. 
The Painter of Sunflowers (in French: Le Peintre de Tournesols) is a portrait of Vincent van Gogh by Paul Gauguin in December 1888.
The portrait was painted when Gauguin visited in Arles.
Van Gogh had asked him to come to Arles, because he wanted to start an art-colony there.
Gauguin however only stayed for two months, because the painters argued. 
Little is known of Van Gogh's activities during the two years he lived with his brother Theo in Paris, 1886-1888.
The fact that he had painted Sunflowers already is only revealed in spring 1889, when Gauguin claimed one of the Arles versions in exchange for studies he had left behind after leaving Arles for Paris.
Van Gogh was upset and replied that Gauguin had absolutely no right to make this request: "I am definitely keeping my sunflowers in question.
He has two of them already, let that hold him.
And if he is not satisfied with the exchange he has made with me, he can take back his little Martinique canvas, and his self-portrait sent me from Brittany, at the same time giving me back both my portrait and the two sunflower canvases which he has taken to Paris.
So if he ever broaches this subject again, I've told you just how matters stand.
"The two Sunflowers in question show two buttons each; one of them was preceded by a small study, and a fourth large canvas combines both compositions.
These were Van Gogh's first paintings with ""nothing but sunflowers""—yet, he had already included sunflowers in still life and landscape earlier.
Sunflowers (original title, in French: Tournesols) are the subject of two series of still life paintings by the Dutch painter Vincent van Gogh.
The earlier series executed in Paris in 1887 depicts the flowers lying on the ground, while the second set executed a year later in Arles shows bouquets of sunflowers in a vase.
In the artist's mind both sets were linked by the name of his friend Paul Gauguin, who acquired two of the Paris versions.
About eight months later Van Gogh hoped to welcome and to impress Gauguin again with "Sunflowers", now part of the painted "décoration" that he prepared for the guestroom of his "Yellow House," where Gauguin was supposed to stay in Arles.
After Gauguin's departure, Van Gogh imagined the two major versions as wings of the "Berceuse Triptych", and finally he included them in his exhibit at Les XX in Bruxelles.