Question: What position in the Nigerian Army is the appointer of Mahmood Yakubu retired from?

full_context: Document 1: Nahzeem Olufemi Mimiko: Nahzeem Olufemi Mimiko born on 1 May 1960 is a Nigerian educational administrator and former vice chancellor of Adekunle Ajasin University, a state-owned university named after the former governor of Ondo State, Nigeria. The university was ranked the best state university by the United State Transparency International Standard (USTIS) in April 2014. Mimiko is the only vice chancellor delegate at the National Conference in Nigeria held in 2014 under the administration of President Goodluck Jonathan. Mimiko assumed office in January 2010 and was preceded by Philip Olayede Abiodun.
Document 2: Theophilus Danjuma: General Theophilus Yakubu Danjuma GCON FSS psc (Rtd) (born 9 December 1938) is a Nigerian Jukun soldier, politician and multi-millionaire businessman and philanthropist. He was Nigerian Army Chief of Army Staff from July 1975 to October 1979. He was also Minister of Defence under Olusegun Obasanjo. Danjuma is chairman of South Atlantic Petroleum (SAPETRO).
Document 3: R.M. Dumuje: Major General Raymond Matthew Dumuje (rtd.) "OFR, fss, mni, psc, BEM" (June 24, 1929 – May 9, 2008) was a prominent Nigerian Army officer and businessman. He became the first Quartermaster general of the Nigerian Army. On February 13, 1976, as a Colonel, he was shot and wounded in Ikoyi, Lagos during the failed "Dimka coup" attempt that saw the assassination of the then Military President, General Murtala Ramat Mohammed. The history of the Nigerian Armed forces records this particular event as a mistaken identity for Lt-General Olusegun Obasanjo, the then Chief of Staff of the Nigerian Army. He was one of very few to have served both in the Nigerian Army and the Nigerian Air Force. He was also a prominent indigene of the "Udu clan" in Delta state. He retired as the Director General, Nigerian Army, Army Reserve and Recruitment, in January 1984.
Document 4: Omar al-Bashir: Omar Hassan Ahmad al-Bashir (Arabic: عمر حسن أحمد البشير‎ ‎ ; pronunciation: ] ; born 1 January 1944) is a Sudanese politician, the seventh president of Sudan and head of the National Congress Party. He came to power in 1989 when, as a brigadier in the Sudanese Army, he led a group of officers in a military coup that ousted the democratically elected government of prime minister Sadiq al-Mahdi after it began negotiations with rebels in the south. Since then, he has been elected three times as President in elections that have been under scrutiny for corruption. In March 2009, al-Bashir became the first sitting president to be indicted by the International Criminal Court (ICC), for allegedly directing a campaign of mass killing, rape, and pillage against civilians in Darfur.
Document 5: Ibrahim Shekarau: Ibrahim Shekarau (born November 5, 1955) was a former Nigeria's minister of education and two term Governor of Kano State in Nigeria. He was elected in April 2003 and reelected in April 2007. He is a member of the People Democratic Party (PDP). He was one of the candidates aspiring to become president in the Nigerian general elections of 2011.
Document 6: Mohammed Shuwa: Mohammed Shuwa (September 1, 1939 – November 2, 2012) was a Nigerian Army Major General and the first General Officer Commanding of the Nigerian Army's 1st Division. Shuwa commanded the Nigerian Army's 1st Division during the Nigerian Civil War. He was murdered in Maiduguri by suspected Boko Haram sect on November 2, 2012.
Document 7: Umaru Mutallab: Alhaji Umaru Abdul Mutallab (born 15 December 1939) is a Nigerian business and banking leader, and former minister of Economic Development under the military government of Murtala Mohammed. He played a major role in introducing Islamic banking into Nigeria. Mutallab was described by "The New York Times" as "among Nigeria's richest and most prominent men," by "The Telegraph" as being "one of Nigeria's most prominent bankers", and by "The Guardian" as being "one of the country's most respected businessmen". Mutallab's son, Umar Farouk Abdulmutallab, is a student who attempted to detonate plastic explosives aboard Northwest Airlines Flight 253 on 25 December 2009.
Document 8: Hosni Mubarak: Muhammad Hosni El Sayed Mubarak (Arabic: محمد حسني السيد مبارك‎ ‎ , ] , "Muḥammad Ḥusnī Sayyid Mubārak "; born 4 May 1928) is a former Egyptian military and political leader who served as the fourth President of Egypt from 1981 to 2011.
Document 9: Muhammadu Buhari: Muhammadu Buhari {'1': ", '2': ", '3': 'GCFR', '4': "} (born 17 December 1942) is the President of Nigeria, in office since 2015. He is a retired major general in the Nigerian Army and previously served as the nation's head of state from 31 December 1983 to 27 August 1985, after taking power in a military "coup d'état". The term Buharism is ascribed to the Buhari military government.
Document 10: Ibrahim Zakzaky: Ibrahim Yaqoub El Zakzaky (alternately Ibraheem Zakzaky; Ibrahim Al-Zakzaky) (born May 5, 1953) is an outspoken Shi'a Muslim cleric in Nigeria, and head of Nigeria's Islamic Movement (IMN). Zakzaky founded the Islamic Movement in the late 1970s, when he was a student at Ahmadu Bello University, and began propagating Shia Islam around 1979, at the time of the Iranian revolution—which saw Iran’s monarchy overthrown and replaced with an Islamic republic under Ayatollah Khomeini. Zakzaky believed that the establishment of a republic along similar religious lines in Nigeria would be feasible. He has been detained several times due to accusations of civil disobedience or recalcitrance under military regimes in Nigeria during the 1980s and 1990s, and is still viewed with suspicion or as a threat by Nigerian authorities. In December 2015, the Nigerian Army raided his residence in Zaria, seriously injured him, and killed hundreds of his followers; since then, he has remained under state detention in the nation's capital pending his release, which was ordered in late 2016.
Document 11: Chief Justice of Nigeria: The Chief Justice of Nigeria or CJN is the head of the judicial arm of the government of Nigeria, and presides over the country's Supreme Court and the National Judicial Council The current Chief Justice is Walter Samuel Nkanu Onnoghen who was appointed by the President on acting capacity after the retirement of Mahmud Mohammed who attained the prescribed retirement age.
Document 12: Mahmood Yakubu: Mahmood Yakubu is a Nigerian academic and current Chairman of the Independent National Electoral Commission (INEC). Subject to approval by the Council of State, Mahmood was appointed to office by President Muhammadu Buhari on 21 October 2015, succeeding Amina Zakari, who served as acting chairman.
Document 13: Andrew Yakubu: Andrew Laah Yakubu (born September 10, 1955) is the former Group Managing Director of the Nigerian National Petroleum Corporation. He is a Fellow of the Nigerian Society of Engineers; Fellow of the Nigerian Society of Chemical Engineers; a Fellow of the Nigerian Association of Technologists in Engineering; Associate Fellow, Chemical Society of Nigeria and a registered Engineer of the Council for the Regulation of Engineering in Nigeria COREN. He was relieved of duty by ex President Jonathan for unknown reasons. The anti-corruption agency, EFCC, recently charged Engr Andrew Yakubu to court for false declaration of assets, after the agency found $9.8m in his Kaduna residence. Andrew Yakubu has not been found guilty by any court of law for corruption in Nigeria.
Document 14: All Progressives Congress: The All Progressives Congress (APC) is a political party in Nigeria, formed on 6 February 2013 in anticipation of the 2015 elections. APC candidate Muhammadu Buhari won the presidential election by almost 2.6 million votes. Incumbent President Goodluck Jonathan conceded defeat on 31 March. This was the first time in Nigeria's political history that an opposition political party unseated a governing party in a general election and one in which power transferred peacefully from one political party to another. In addition, the APC won the majority of seats in the Senate and the House of Representatives in the 2015 elections, though it fell shy of winning a super-majority to override the ability of the opposition People's Democratic Party to block legislation.
Document 15: Kawu Sumaila: Suleiman AbdulRahaman also knows as Kawu Sumaila (born March 3, 1968) is the SSA to President Buhari on National Assembly House of Representatives Matters appointed 27 August 2015. He was a three term member of Nigeria House of Representatives and held the position of Deputy Minority Leader of the 6th and 7th House of Representatives of Nigeria. He was an All Progressive Congress (APC) member and served as member of the board of trustees, National Caucus, and NEC and served as member of central merger committee which formed APC
ground_truth: major general