[1] https://www.bbc.com/news/world-us-canada-41850798
[2] https://www.politico.com/magazine/story/2017/11/02/clinton-b...
This is incorrect. Clinton had a majority of the pledged (primary/caucus-determined) delegates, though not an absolute majority of all delegates based on super delegates alone.
The early huge advantage in unpledged “superdelegates” played a role in media coverage and the perception of inevitability, and no doubt helped her win, but she got more of the delegates selected by voters than Sanders did.
This is the rigging that took place.
The DNC was hacked and the emails released to hurt Hillary Clinton and to aid the Trump campaign. It is not yet known if the Trump campaign was involved, but it is a fact that the emails were released to aid his campaign. Here are some links:
Guccifer 2.0 is the hacker involved in the DNC emails.
https://www.cnn.com/2016/09/13/politics/guccifer-2-0-democra...
Guccifer 2.0 linked to Russian government.
https://arstechnica.com/tech-policy/2018/03/dnc-lone-hacker-...
CIA director calls WikiLeaks Russia-aided "non-state hostile intelligence service"
https://www.cbsnews.com/news/cia-director-calls-wikileaks-a-...
Wikileaks telling Trump campaign they should give them tax returns so that they don't look so biased for Russia
https://www.theatlantic.com/politics/archive/2017/11/the-sec...
DNC emails released one hour after Access Hollywood tapes
https://www.cnn.com/2017/10/07/politics/one-year-access-holl...
Russia's hate of Clinton is due to the Magnitsky Act, which targets oligarchs in Russia.
https://www.vice.com/en_us/article/8qbbdx/why-putin-hates-cl...