Three-time champion passed away just before last year's Monaco Grand Prix at the age of 70
Mercedes driver added he felt this season had been his hardest year to date in fighting to win the championship
Bottas won the typhoon-affected Japanese Grand Prix, meaning that Mercedes sealed a sixth title in a row
Triple world champion, best remembered for his comeback from a fiery crash in 1976 died last week at the age of 70
Three-time world champion and non-executive director of the all-conquering Mercedes team, died last Monday, aged 70
Austria was non-executive chairman of the Mercedes team when he died on Monday night at the age of 70
Three-times Formula One champion suffered from influenza and had a lung transplant last August
Three-times Formula One champion died at 70 after battling declining health
Austrian won two world championships in 1975 and 1977 with Ferrari and a third in 1984 with McLaren