Problem: Iron Maiden are an English heavy metal band formed in Leyton, East London, in 1975 by bassist and primary songwriter Steve Harris. The band's discography has grown to thirty-eight albums, including sixteen studio albums, twelve live albums, four EPs, and seven compilations. Pioneers of the new wave of British heavy metal, Iron Maiden achieved initial success during the early 1980s. After several line-up changes, the band went on to release a series of UK and US platinum and gold albums, including 1982's The Number of the Beast, 1983's Piece of Mind, 1984's Powerslave, 1985's live release Live

On New Year's Eve 1978, Iron Maiden recorded a demo, consisting of four songs, at Spaceward Studios in Cambridge. Hoping the recording would help them secure more gigs, the band presented a copy to Neal Kay, then managing a heavy metal club called "Bandwagon Heavy Metal Soundhouse", located in Kingsbury Circle, northwest London. Upon hearing the tape, Kay began playing the demo regularly at the Bandwagon, and one of the songs, "Prowler", eventually went to No. 1 in the Soundhouse charts, which were published weekly in Sounds magazine. A copy was also acquired by Rod Smallwood, who soon became the band's manager, and, as Iron Maiden's popularity increased, they released the demo on their own record label as The Soundhouse Tapes, named after the club. Featuring only three tracks (one song, "Strange World", was excluded as the band were unsatisfied with its production) all five thousand copies were sold out within weeks.  In December 1979, the band secured a major record deal with EMI and asked Dave Murray's childhood friend Adrian Smith of Urchin to join the group as their second guitarist. Smith declined as he was busy with his own band, Urchin, so Iron Maiden hired guitarist Dennis Stratton instead. Shortly afterwards, Doug Sampson left due to health issues and was replaced by ex-Samson drummer Clive Burr at Stratton's suggestion on 26 December. Iron Maiden's first appearance on an album was on the Metal for Muthas compilation (released on 15 February 1980) with two early versions of "Sanctuary" and "Wrathchild". The release led to an ensuing tour which featured several other bands linked with the new wave of British heavy metal.  Iron Maiden's eponymous 1980 release, Iron Maiden, debuted at No. 4 in the UK Albums Chart. In addition to the title track (a live version of which would be one of the first music videos aired on MTV), the album includes other early favourites such as "Running Free", "Transylvania", "Phantom of the Opera", and "Sanctuary" - which was not on the original UK release but appeared on the US version and subsequent remasters. The band set out on a headline tour of the UK, before opening for Kiss on their 1980 Unmasked Tour's European leg as well as supporting Judas Priest on select dates. Iron Maiden also appeared, to much acclaim, at the Reading Festival 1980. They were second to top of the bill on the Saturday, with UFO headlining. After the Kiss tour, Dennis Stratton was dismissed from the band as a result of creative and personal differences, and was replaced by Adrian Smith in October 1980.  In 1981, Iron Maiden released their second album, entitled Killers. Containing many tracks written prior to their debut release, only two new songs were written for the record: "Prodigal Son" and "Murders in the Rue Morgue" (the latter's title was taken from the short story by Edgar Allan Poe). Unsatisfied with the production on their debut album, the band hired veteran producer Martin Birch, who would go on to work for Iron Maiden until his retirement in 1992. The record was followed by the band's first world tour, which included their debut performance in the United States, opening for Judas Priest at The Aladdin Casino, Las Vegas.

what happened in 1981?

Answer with quotes: In 1981, Iron Maiden released their second album, entitled Killers.

Question:
Ara Raoul Parseghian (May 21, 1923 - August 2, 2017) was an American football player and coach who guided the University of Notre Dame to national championships in 1966 and 1973. He is noted for bringing Notre Dame's Fighting Irish football program from years of futility back into a national contender in 1964 and is widely regarded alongside Knute Rockne and Frank Leahy as a part of the "Holy Trinity" of Notre Dame head coaches. Parseghian grew up in Akron, Ohio, and played football beginning in his junior year of high school. He enrolled at the University of Akron, but soon quit to join the U.S. Navy for two years during World War II.
Parseghian quickly turned things around in 1964; he re-established a sense of confidence and team spirit that had been lost under Kuharich and Devore. Practices were carefully planned and organized with the help of a coaching staff that consisted of three assistants from Northwestern and four former Notre Dame players. Parseghian listened to players' concerns about the program and addressed them. He invigorated the team's offense by favoring passing and bringing in smaller and quicker players. A rule change allowing unlimited substitutions starting in 1964 helped make this strategy successful; fast-running receivers could now be taken out of the game and rested as others replaced them.  Parseghian also recognized talent in quarterback John Huarte and wide receiver Jack Snow, who had been used only sparingly for two seasons by previous coaches. Huarte could throw far and accurately but was soft-spoken, a trait Parseghian and his staff helped change. Snow was large for a receiver of his era, but Parseghian thought his athleticism and sure hands would make him a good wideout. Still, expectations were muted for the 1964 season: Parseghian told his coaches that the team would have a 6-4 record if they were lucky. Sports Illustrated predicted a 5-5 record at best, and the team did not rank among the top 20 programs in the country in the pre-season AP Poll.  Notre Dame nonetheless opened the season with a 31-7 victory over heavily favored Wisconsin, a game in which Huarte threw for more yards than the team's leading passer had over the entire 1963 season. Notre Dame players carried Parseghian off the field after the win, which vaulted the team to ninth place in the polls. A string of victories followed, first against Purdue and then Air Force and UCLA. Notre Dame rose to first place in the national polls following a 40-0 win over Navy in October. The team went undefeated until the last game of the year against USC, who won 20-17 in the final minutes on a touchdown pass from Craig Fertig to Rod Sherman. The loss unseated Notre Dame from the top ranking in the national polls, but the team still won the MacArthur Trophy, a championship awarded by the National Football Foundation.  Huarte passed for 2,062 yards and set 12 school records in 1964, four of which still stood as of 2009. He also won the Heisman Trophy. Snow led the country in receptions, with 60. Parseghian, meanwhile, won numerous coach of the year awards for engineering the turnaround, including from the American Football Coaches Association, the Football Writers Association of America, the Washington Touchdown Club, the Columbus Touchdown Club, and Football News.  Huarte and Snow graduated after the 1964 season, and Notre Dame felt their absence the following year, posting a 7-2-1 record. While the team did not contend for a national title, defensive back Nick Rassas led the nation in punt returns and came in sixth in interceptions; he was named a first-team All-American by sportswriters.
Answer this question using a quote from the text above:

Who were the players he brought in?

Answer:
quarterback John Huarte and wide receiver Jack Snow,