JOHANNESBURG (AP) -- Most of Nelson Mandela's handwriting is neat, but it harbors a few mysteries. Archivists sometimes struggle to decipher words in the vast body of documents that Mandela penned, and he often jotted an acronym that nobody, not even the former South African president in later years, has been able to explain.
Now, some of the words that Mandela wrote, which help define the man who led the fight against white rule and became president after apartheid, are on display at the Nelson Mandela Foundation, which on Monday unveiled a public facility.
Mandela, now 95 and critically ill, wrote prolifically during his storied career.
In jail, Mandela's associates wrote some things in tiny script, reducing the amount of paper used so that it could be smuggled out of prison more easily. In his autobiography, "Long Walk to Freedom," Mandela notes his copy of the book manuscript was confiscated by authorities, but applauds fellow prisoners with "unique calligraphic skills" who helped get the original manuscript out of prison.
Mandela was a lawyer early in his career, and some letters to family from prison balance sadness with hope and optimism, with carefully chosen words.
"He doesn't shoot from the hip," said Razia Saleh, a senior archivist at the foundation.
Mandela, also known by his clan name Madiba, was released in 1990 after 27 years in apartheid prisons, and many of the notes he wrote since then include the initials KLM. Nobody at the foundation can figure out its meaning.
"Madiba hasn't been able to tell us what it means," Saleh said. "So that's a mystery. Maybe somebody can solve it at some point."
The former president's orderly handwriting stems from his education in Christian mission schools, though it's sometimes hard for archivists to make out letters such as "s'' and "h'' in Mandela missives.
"We've transcribed his desk calendars, and sometimes we battle to make out words," Saleh said.
The display at the non-profit Nelson Mandela Foundation is open by appointment and includes a small piece of stone from the hut where Mandela was born in the rural village of Mvezo in Eastern Cape province. The hut was demolished a few years ago to make way for new construction.
"There isn't much that survived from his early childhood. There's no photograph. We don't have a birth certificate," said Saleh. The stone, she added, is "one of the few things that's tangible, that links us to Madiba's early life."
The opening of the public facility coincides with the 20th anniversary of the approval of an interim constitution and an electoral bill that set the stage for South Africa's first all-race elections in 1994.
Mandela now stays in a big house in a Johannesburg neighborhood near the center named after him, attended by doctors. President Jacob Zuma visited him on Monday, and the president's office said Mandela remains in stable but critical condition.
The Sunday Independent, a South African newspaper, quoted Mandela's former wife, Winnie Madikizela-Mandela, as saying he is unable to speak because of tubes that keep his lungs clear of fluid. Mandela has been in intensive medical care at his home since Sept. 1, when he was discharged after nearly three months in a hospital for a recurring lung infection.
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