Question: Where was pho possibly first mentioned in English writing?
About the article "Pho", section "Etymology and origins".

Candidate passages:
Reviews of 19th and 20th century Indochinese literature have found that pho entered the mainstream sometime in the 1910s.
Georges Dumoutier's extensive 1907 account of Vietnamese cuisine omits any mention of pho, while Nguyễn Công Hoan recalls its sale by street vendors in 1913.
A 1931 dictionary is the first to define ' as a soup: "from the word '.
A dish consisting of small slices of rice cake boiled with beef.
"Possibly the earliest English-language reference to pho was in the book "Recipes of All Nations", edited by Countess Morphy in 1935: In the book, pho is described as "an Annamese soup held in high esteem ... made with beef, a veal bone, onions, a bayleaf, salt, and pepper, and a small teaspoon of "nuoc-mam"".
"There are two prevailing theories on the origin of the word "" and, by extension, the dish itself.
As author Nguyễn Dư notes, both questions are significant to Vietnamese identity.
Luang Pho Waen Sujinno (, RTGS: Luang Pu Waen Su-Chin-No, also Phra Ajahn Waen Sujinno, popularly known as Luang Pho Waen meaning Venerable Grandfather; 16 February 1887 – 2 July 1985) is one of the longest living students of Phra Ajahn Mun Bhuridatta and was a very popular monk in Thailand.
Luang Pho Waen Sujinno was also featured in the Asia Magazine.
Another true ascetic at heart, he led the thudong life until the point where he could not physically travel any more and had to settle in a forest monastery in the Chiang Mai region.
Luang Pho Waen Sujinno was a revered monk, highly skilled in Samadhi and Dhamma.
The most remarkable characteristic of Luang Pho Waen was his dislike of crowded places.
He loved to live alone in the forests away from people and urbanized areas just like his teacher, Ajahn Mun Bhuridatta.
Some people said that Luang Pho Waen had achieved Arahant level.
Tahn Joo Koon Noh had in fact mentioned that "There is a Phra Arahant, but he lives far away, in the forest". 
Lipice was first mentioned in writing it 1638. 
In the aftermath of the Vietnam War, Vietnamese refugees brought pho to many countries.
Restaurants specializing in pho appeared in numerous Asian enclaves and Little Saigons, such as in Paris and in major cities in Canada, the United States, and Australia.
In the United States, pho began to enter the mainstream during the 1990s, as relations between the U.S. and Vietnam improved.
At that time Vietnamese restaurants began opening quickly in Texas and California, spreading rapidly along the Gulf and West Coasts, as well as the East Coast and the rest of the country.
During the 2000s, pho restaurants in the United States generated US$500 million in annual revenue, according to an unofficial estimate.
Pho can now be found in cafeterias at many college and corporate campuses, especially on the West Coast.
The word pho was added to the "Shorter Oxford English Dictionary" in 2007.
Pho is listed at number 28 on "World's 50 most delicious foods" compiled by "CNN Go" in 2011. 
Pho originated in the early 20th century in northern Vietnam, apparently southeast of Hanoi in Nam Định Province, then a substantial textile market.
The traditional home of pho is reputed to be the villages of and (or ) in Đông Xuân commune, Nam Trực District, Nam Định Province.
According to villagers, pho was eaten in long before the French colonial period when it was popularized.
Pho was originally sold at dawn and dusk by roaming street vendors, who shouldered mobile kitchens on carrying poles (').
From the pole hung two wooden cabinets, one housing a cauldron over a wood fire, the other storing noodles, spices, cookware, and space to prepare a bowl of pho.
Pho vendors kept their heads warm with distinctive, disheveled felt hats called '.
Hanoi's first two fixed pho stands were a Vietnamese-owned Cát Tường on Cầu Gỗ Street and a Chinese-owned stand in front of Bờ Hồ tram stop.
They were joined in 1918 by two more on Quạt Row and Đồng Row.
Around 1925, a Vân Cù villager named Vạn opened the first "Nam Định style" pho stand in Hanoi. ""
declined in number around 1936–1946 in favor of stationary eateries.