Email from Tan Choo Eng to the 5th Earl of Cranbrook concerning starting a swiftlet house-farm in Penang at a cost of RM150,000. It had three nests

Email from Tan Kok Yang to the 5th Earl of Cranbrook informing how unlikely the developers would keep the nesting site of the swiftlets at Sentosa Island

Email from Tan Kok Yang to the 5th Earl of Cranbrook seeking his advice on how to care for swiftlets at Bukit Imbiah, Sentosa Island

Email from Tan Kok Yang to the 5th Earl of Cranbrook thanking him for his advice on how to care for swiftlets at Bukit Imbiah, Sentosa Island. Tan mentioned another swiftlet colony at an old bungalow at another part of Sentosa which was being converted into a resort and sought for advice on the swiftlets there

Email from the 5th Earl of Cranbrook to an unknown person concerning his group's wish to tour Sungai Mahakam and Tanjung Selur, Bulungan

Email from the 5th Earl of Cranbrook to Charles Leh Moi Un asking him for two other locations

Email from the 5th Earl of Cranbrook to Charles Leh Moi Un asking him which town the the swiftlets inside bird-houses were taken

Email from the 5th Earl of Cranbrook to Chris Stimpson commenting on his attached manuscript, "Results from the preliminary investigation of the utility of biometrics for the identification of swiftlet (Apodidae) carpometacarpi recovered from archaeological deposits in the Niah Caves, Sarawak"

Email from the 5th Earl of Cranbrook to Dale Clayton describing his team's attempt to get to Sangrio Cave in 2014; his team's visit to Loksimpul cave in 2014 and 2016

Email from the 5th Earl of Cranbrook to Dr David Willard attaching a letter with file name FMNH Curator of Birds1