Question: What blowback-operated semi-automatic pistols have a similar design to Astra A-60?
Context: The Intratec TEC-9, TEC-DC9, or AB-10 is a blowback-operated semi-automatic pistol.  It was designed by Intratec, an American offshoot of Interdynamic AB.  The TEC-9 was made of inexpensive molded polymers and a mixture of stamped and milled steel parts.  The simple design of the gun made it easy to repair and modify. The FN Baby Browning is a small blowback-operated semi-automatic pistol designed by Dieudonné Saive based on a design by John Browning (among Browning's last designs) and chambered in .25 ACP (6.35×16mmSR).  The pistol features a six-round magazine capacity and is a striker-fired, single action, blow back mechanism.  The manual thumb operated safety locks the slide in the closed position when engaged using side thumb pressure. Mexicans have a right to own firearms, but legal purchase from the single Mexican gun shop in Mexico City, controlled by the Army, is extremely difficult.  Guns smuggled into Mexico are sometimes obtained at gunshops in the United States and carried across the US-Mexico border.  In other cases the guns are obtained through Guatemalan borders or stolen from the police or military.  Consequently, black market firearms are widely available.  Many firearms are acquired in the U.S. by women with no criminal history, who transfer their purchases to smugglers through relatives, boyfriends and acquaintances and then smuggled to Mexico a few at a time.  The most common smuggled firearms include AR-15 and AK-47 type rifles, and FN 5.7 caliber semi-automatic pistols.  Many firearms are purchased in the United States in a semi-automatic configuration before being converted to fire as select fire machine guns.  Mexico seized in 2009 a combined total of more than 4,400 firearms of the AK-47 and AR-15 type, and 30% of AK-47 type rifles seized have been modified to select fire weapons, effectively creating assault rifles. Roth–Theodorovic pistols were a series of prototypes sometimes identified with model years including 1895, 1897 and 1898.  These long-recoil, locked-breech, single or double-action semi-automatic pistols were designed by Austrian inventor Wasa Theodorovic with the financial support of George Roth.  Early versions were unusually large with an oversize trigger guard and an elongated grip.  The internal magazine was top loaded from a stripper clip.  A group of 25 pistols submitted for Austrian military trials brought no orders.  The design saw numerous modifications including a shorter grip, a decocker, a Tambour grip safety, and a rotating and swiveling ring for attaching a lanyard.  Later modifications were made by inventor Karel Krnka.  Although these prototypes never entered mass production, some of their features were later incorporated into such successful models as the Frommer Stop and the Roth–Steyr M1907. The Walther PP ("Polizeipistole", or police pistol) series pistols are blowback-operated semi-automatic pistols, developed by the German arms manufacturer Walther. The Steyr M is a series of semi-automatic pistols developed by Steyr Mannlicher GmbH & Co KG of Austria for police services and the civilian shooting market.  Design work on the new pistol began in the early 1990s and the final product known as the M9 (adapted to fire the 9×19mm Parabellum cartridge) was officially unveiled in the spring of 1999.  The M40 version chambered in .40 S&W was developed before the M9, followed later by the M357 (caliber .357 SIG or 9×22mm) and two smaller variants of the M9 and M40 designated the S9 and S40 respectively.  These pistols were developed primarily for concealed carry and have a shortened barrel, slide, smaller frame and a reduced magazine capacity.  In 2013 the Steyr M (Medium) and S (Small) form factors were complemented by the L (Large) sized series and the C (Compact) sized series both available in 9×19mm Parabellum and .40 S&W chamberings as the L9-A1, L40-A1, C9-A1 and C40-A1. The Calico Liberty is a roller-delayed blowback-operated semi-automatic rifle (Liberty II) or pistol (Liberty III) chambered for the 9 mm Para round, designed by Calico Light Weapons Systems.  These firearms use an unusual 50 or 100-round helical magazine that allow for a large number of rounds in a relatively compact and convenient package.  The spent cartridges are discharged in an unusual fashion as well: downward, ahead of the trigger guard.  This makes it relatively easy to fit an effective device to catch the cartridge cases, which can then be reloaded.  A full-automatic (machine gun) version is available for military, police and other government agencies. The M100 is a blowback-operated semi-automatic rifle chambered in .22 LR, manufactured by Calico Light Weapons Systems in Hillsboro, Oregon, United States.  It was originally designed and released in the 1980s to be of use to Law Enforcement and Military markets due to its slim profile. The Astra A-60 is a double-action,single-action, semi-automatic pistol at one time produced in Spain by Astra-Unceta y Cia SA.  The design is similar to the Walther PP and features a slide-lock release lever. The Nambu pistols (南部拳銃 or 南部大型自動拳銃 , Nanbu kenjuu or Nanbu ōgata jidou-kenjuu ) were a series of semi-automatic pistols produced by the Japanese company Koishikawa Arsenal later known as the Tokyo Artillery Arsenal.  The series had five variants, the Type A Model 1902 (also called the Grandpa Nambu), the Type A Model 1902 Modified (also known as the Papa Nambu), the Type B (also known as the Baby Nambu), the Type 14 (南部十四年式自動拳銃) and the Type 94.  The pistols were designed by Kijiro Nambu and saw extensive service during the Russo-Japanese War, Second Sino-Japanese War and World War II.  The Type A was made in very small numbers.  Type A Modified and Type B Nambus were never formally adopted by any branch of the armed forces of Imperial Japan but were sold to officers through officer stores.  The Type 14 was adopted as an official sidearm.  As World War II progressed, and particularly in the final year of the war, in order to speed production, Type 14s began to be more hastily manufactured with a subsequent decline in quality.
Answer: Walther PP