Fascinating, thanks for posting this. I couldn't find the full paper but I found a longer excerpt with a more detailed description:
http://eurekamag.com/research/025/432/seed-progeny-vegetative-hybrid-mandarin-siva-mikan-citrangequat.php
The following expt. was carried out at the Exptl. Station of Subtropical and Southern Fruit Crops at Sotchi. A bud from the mandarin, Siva-Mikan, having a small, early-ripening fruit, was grafted on to a branch of a citrangequat, a hybrid product of orange, trifoliate orange and kum-quat. When the shoot which grew from the bud was about 25 cm. long, its tip was grafted into another branch above it. Both ends of the shoot were thus grafted into different branches of the same stock plant. After 2 yrs. the shoot formed buds, the leaves from which were removed, as they appeared, and the flowers protected by parchment to ensure them being fertilized only by their own pollen. The flowering periods of the stock and scion do not coincide and the pollen of citrangequat has so far proved to be ineffective, attempts to obtain hybrids by dusting it on lemon flowers have never yet succeeded. Though deprived of its leaves, the scion produced 10 fully matured fruits. These fruits had been wholly nourished from the stock and had acquired some of the outward characteristics of its fruit. The 10 fruits produced 3 seeds which were sown in winter in pots placed in a warm greenhouse. Only 1 seed germinated. At first the seedling plant showed none of the morphological characteristics of a citrangequat but in the 2d half of July its leaves began to assume them. Indeed, it came to have a closer resemblance to the citrangequat than to the mandarin.
