Awwal 29, 1432 H/March 4, 2011, SPA -- Zimbabwean President Robert Mugabe has flown back to Singapore, for the fourth time in just over two months, for a follow-up health check after his cataract surgery, it was reported Friday. According to dpa, Mugabe left Thursday for a "final check-up," which was a medical formality and not a cause for alarm, state media quoted his spokesman George Charamba as saying. The 87-year-old president was expected back in Zimbabwe on Sunday, Charamba said.