The most reliable source of vitamin B-12 for vegans is fortified foods or supplements specifically designed for vegans, as plant-based foods do not naturally contain sufficient amounts of vitamin B-12.
Mango
meat
Plenty of fresh, organic, unprocessed vegetables, fruits, legumes, nuts, seeds, and grains, along with lots of water. Also, find a source of vitamin B-12, such as fortified soy milk, nutritional (brewer's) yeast, or a single or multi-vitamin supplement.
B12 is mentioned by most nutritionists. Protein and calcium, although not vitamins, are available in less quantities in vegan food. I'm a vegetarian so I would highly recommend B12 and Vitamin D. Be sure to take in enough proteins and calcium so you don't become malnourished as well.
It's not the most reliable source.
sunlight
The water provided by one's city or region is the most reliable source of dietary flouride.
The most reliable source for a 240 wiring diagram is the manufacturer's official website or manual.
The internet is not the most reliable but sometimes the only source, as some information can only be found there.
Everybody knows, the most reliable source of information if the AnswersWiki of Answers.com. Or reading from goats intestines ...
The most reliable source to find a Hilton Head vacation rental is www.rentals.com. Another reliable website is www.rentalsource.com/5051415
The fruit inself is a sufficient source of Vitamin C. In fact most fruits and some vegetables are good sources of Vitamin C.